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National Boards => General Highway Talk => Topic started by: webny99 on April 11, 2020, 05:28:03 PM

Title: Counties with NO Direct Routes to Other States
Post by: webny99 on April 11, 2020, 05:28:03 PM
Quote from: webny99 on April 11, 2020, 05:04:52 PM
I believe some of the remaining counties have zero connections to any other state... which gets me thinking...

... in figuring out which counties in New York are directly connected by numbered route to Pennsylvania, I discovered something interesting. Several of our counties actually have ZERO direct numbered highway connections to any other state.

48 of New York's 62 counties have direct connections to Pennsylvania.
Of the 14 that don't, 9 have direct routes to other bordering states, and a 10th (Hamilton County) has NY 30, a direct route to Quebec.

That leaves just 4 counties, Suffolk, Nassau, Lewis and Orleans*, with no direct routes to anywhere out of state.
How many such counties are there in your state?
Title: Re: Counties with NO Direct Routes to Other States
Post by: webny99 on April 11, 2020, 05:31:20 PM
*Orleans County is up for debate as to whether NY 104, which ends at the Rainbow International Bridge to Canada, constitutes a direct connection to Ontario. The bridge itself is unnumbered, but you can proceed straight from NY 104 onto the bridge (https://www.google.com/maps/@43.0891606,-79.0630749,3a,59.8y,225.24h,81.18t/data=!3m7!1e1!3m5!1sc-vbA8aPyMSD9-a8d4Ajiw!2e0!6s%2F%2Fgeo2.ggpht.com%2Fcbk%3Fpanoid%3Dc-vbA8aPyMSD9-a8d4Ajiw%26output%3Dthumbnail%26cb_client%3Dmaps_sv.tactile.gps%26thumb%3D2%26w%3D203%26h%3D100%26yaw%3D241.95757%26pitch%3D0%26thumbfov%3D100!7i13312!8i6656), no turns involved.
Title: Re: Counties with NO Direct Routes to Other States
Post by: Roadgeekteen on April 11, 2020, 05:43:00 PM
Two in Massachusetts. Not surprisingly, they are Dukes county and Nantucket county.
Title: Re: Counties with NO Direct Routes to Other States
Post by: NWI_Irish96 on April 11, 2020, 05:54:09 PM
Indiana has only one: Ohio County
Title: Re: Counties with NO Direct Routes to Other States
Post by: webny99 on April 11, 2020, 06:00:53 PM
Quote from: cabiness42 on April 11, 2020, 05:54:09 PM
Indiana has only one: Ohio County

Obviously there are no Ohio River crossings within the county, but even so, bonus points for being a border county!
Title: Re: Counties with NO Direct Routes to Other States
Post by: Crown Victoria on April 11, 2020, 06:40:48 PM
Pennsylvania has just one:  Cameron County
Title: Re: Counties with NO Direct Routes to Other States
Post by: jeffandnicole on April 11, 2020, 06:45:22 PM
Looks like Cumberland County, NJ, qualifies...barely.  It comes within 1/3 of a mile of US 40.
Title: Re: Counties with NO Direct Routes to Other States
Post by: TheHighwayMan3561 on April 11, 2020, 07:04:44 PM
I thought Minnesota would have none, but Isanti County proved me wrong. It comes within a hair of not qualifying where MN 95 meets US 8 right at the river in Taylors Falls.
Title: Re: Counties with NO Direct Routes to Other States
Post by: hbelkins on April 11, 2020, 07:22:24 PM
I'm in a pretty good cluster of Kentucky counties with no US or Interstate routes, or state routes that cross a border.
Title: Re: Counties with NO Direct Routes to Other States
Post by: cu2010 on April 11, 2020, 07:33:21 PM
Quote from: webny99 on April 11, 2020, 05:28:03 PM
Quote from: webny99 on April 11, 2020, 05:04:52 PM
I believe some of the remaining counties have zero connections to any other state... which gets me thinking...

... in figuring out which counties in New York are directly connected by numbered route to Pennsylvania, I discovered something interesting. Several of our counties actually have ZERO direct numbered highway connections to any other state.

48 of New York's 62 counties have direct connections to Pennsylvania.
Of the 14 that don't, 9 have direct routes to other bordering states, and a 10th (Hamilton County) has NY 30, a direct route to Quebec.

That leaves just 4 counties, Suffolk, Nassau, Lewis and Orleans*, with no direct routes to anywhere out of state.
How many such counties are there in your state?
Quote from: webny99 on April 11, 2020, 05:31:20 PM
*Orleans County is up for debate as to whether NY 104, which ends at the Rainbow International Bridge to Canada, constitutes a direct connection to Ontario. The bridge itself is unnumbered, but you can proceed straight from NY 104 onto the bridge (https://www.google.com/maps/@43.0891606,-79.0630749,3a,59.8y,225.24h,81.18t/data=!3m7!1e1!3m5!1sc-vbA8aPyMSD9-a8d4Ajiw!2e0!6s%2F%2Fgeo2.ggpht.com%2Fcbk%3Fpanoid%3Dc-vbA8aPyMSD9-a8d4Ajiw%26output%3Dthumbnail%26cb_client%3Dmaps_sv.tactile.gps%26thumb%3D2%26w%3D203%26h%3D100%26yaw%3D241.95757%26pitch%3D0%26thumbfov%3D100!7i13312!8i6656), no turns involved.

NY812 ends at the Ogdensburg-Prescott International Bridge, so Lewis County has a direct route to Canada.
Title: Re: Counties with NO Direct Routes to Other States
Post by: oscar on April 11, 2020, 07:40:34 PM
You wouldn't think it, but Alaska has several counties/equivalents with a direct link to Washington state, via one of the Alaska Marine Highway auto ferries (when they're running -- right now the two vessels able to make that run are scheduled to return to service next month). These include Kenai Peninsula, Yakutat, Skagway, Haines, Juneau, and Ketchikan Gateway boroughs, maybe also Petersburg and Wrangell boroughs (depending on whether the tides are high enough for safe passage through the Wrangell Narrows), and the new Chugach census area in Prince William Sound.

The other 21 Alaska county equivalents have no road connections at all, or travelers have to pass through Canada on multiple highways. Technically, the above-mentioned ferries run through Canadian waters, but no stops or customs inspections in Canada, so it's as if you never leave the United States.
Title: Re: Counties with NO Direct Routes to Other States
Post by: Thing 342 on April 11, 2020, 07:44:25 PM
Virginia:

City of Hopewell
City of Manassas
City of Manassas Park
City of Poquoson

Charles City County
King and Queen County
King William County
Mathews County
Northumberland County
Richmond County
Westmoreland County
Title: Re: Counties with NO Direct Routes to Other States
Post by: gonealookin on April 11, 2020, 07:58:33 PM
Since all of Nevada's 16 counties plus the independent city of Carson City are served by either a US highway or an interstate that crosses into another state, there aren't any here.

Incidentally neither US 50 nor US 6 is needed on these lists for Nevada.  I-80 hits 9 of the 16 counties, US 93 adds 3 more, US 95 3 more beyond that and finally US 395 passes through Carson City and Douglas County.
Title: Re: Counties with NO Direct Routes to Other States
Post by: Flint1979 on April 11, 2020, 08:03:14 PM
Michigan has some. I know in my area that Gladwin, Midland, Tuscola, Sanillac and Huron don't have any routes that connect to another state. That's just a start for Michigan. My county has I-75 and US-23 that connect to Ohio and I-75 to Ontario, Canada.
Title: Re: Counties with NO Direct Routes to Other States
Post by: Scott5114 on April 11, 2020, 08:24:59 PM
There are only four counties in Oklahoma with no routes shared in common in Texas: Alfalfa, Haskell, Latimer, and Pawnee. Of these, Alfalfa and Pawnee both contain US-64 (shared with New Mexico and Arkansas) and Latimer contains US-270 (shared with Kansas and Arkansas).

That leaves just Haskell County, the only county in Oklahoma with no Interstate or US routes. It contains SH-9, which ends at the Texas and Arkansas state lines on either side. Neither side connects to a state route 9, however (TX-203 on the TX side and I-540 in AR).

So the answer for Oklahoma would be "Haskell" if you don't count SH-9 as being a direct route to another state and "none" if you do.
Title: Re: Counties with NO Direct Routes to Other States
Post by: webny99 on April 11, 2020, 08:34:36 PM
Quote from: cu2010 on April 11, 2020, 07:33:21 PM
NY812 ends at the Ogdensburg-Prescott International Bridge, so Lewis County has a direct route to Canada.

Good point! Figured there was going to be something I forgot or overlooked.

So we're left with just Nassau and Suffolk if we count connections to Canada, and add Lewis, Orleans, and Hamilton if we don't.
Title: Re: Counties with NO Direct Routes to Other States
Post by: bassoon1986 on April 11, 2020, 09:32:15 PM
Louisiana has fewer than I would have thought. Only 2 and they are the most southeast in the state, with numbered routes mostly terminating in New Orleans and no further. Because LA 1 reaches so far south and US 90 dips to catch most of the coastal parishes, all but St Bernard and Plaquemines parishes are connected.


iPhone
Title: Re: Counties with NO Direct Routes to Other States
Post by: TheStranger on April 11, 2020, 09:46:10 PM
In California, Trinity County used to be this, but when State Route 299 (supplanting the former US 299) was extended to connect to a dirt road in Nevada, it no longer counts.

Lake County however does (Route 29, 175, 20, 53 all do not lead to a state border).

Butte County looks like it does now (state route 99, 70, 149, 191, 32, 162); prior to 1964 however 99 was US 99E and 70 at the time was Alternate US 40, the latter of which did cross into Nevada and the former of which was part of the multi-state US 99.

Because of the 1964 decommissioning of US 99E and Alternate US 40, Yuba County now also fits this category (99, 65, 70, 49, 20).

Tulare County fits this category specifically because the two segments of Route 190 have never been joined together.  Madera County fits due to US 99 becoming Route 99.

Mariposa County and Tuolumne County qualify as Route 120 ends at US 6 just a few miles from the Nevada state line.

Calaveras County also seems to be in this category.
Title: Re: Counties with NO Direct Routes to Other States
Post by: webny99 on April 11, 2020, 09:59:48 PM
Quote from: TheStranger on April 11, 2020, 09:46:10 PM
In California, Trinity County used to be this, but when State Route 299 (supplanting the former US 299) was extended to connect to a dirt road in Nevada, it no longer counts.

Well, as long as the dirt road is at least a numbered state highway. If it's less than that, I would say the county still counts.
Title: Re: Counties with NO Direct Routes to Other States
Post by: Konza on April 12, 2020, 02:22:45 AM
The only county in Arizona that is not served by a highway that crosses a state line without changing its number is Santa Cruz County, the county seat of which is Nogales.

Obviously Nogales is the south endpoint of Interstate 19, and was the south endpoint of US 89 (and MSR 789) before it was (they were) truncated.  But I-19 becomes Mexico Federal Highway 15 at the International Border...
Title: Re: Counties with NO Direct Routes to Other States
Post by: US 89 on April 12, 2020, 02:44:37 AM
Every county in Utah with an Interstate or US highway has a direct connection to another state, which accounts for 28 of the 29 counties. That leaves Wayne County, which only has four state-level numbered routes: SR 12, 24, 72, and 95. None of those reach a state line, so Wayne is the only Utah county to qualify for this thread.
Title: Re: Counties with NO Direct Routes to Other States
Post by: GaryV on April 12, 2020, 08:22:10 AM
Quote from: Flint1979 on April 11, 2020, 08:03:14 PM
Michigan has some. I know in my area that Gladwin, Midland, Tuscola, Sanillac and Huron don't have any routes that connect to another state. That's just a start for Michigan. My county has I-75 and US-23 that connect to Ohio and I-75 to Ontario, Canada.
You aren't counting the Badger as part of US-10?  That would eliminate Midland.

In the UP, I see only Luce County not having a single State/US/Interstate highway connection to another state.  Although if I recall correctly, at one time M-28 was concurrent with US-2 into Wisconsin, so historically it would not have qualified.

In the Lower Peninsula I add Montmorency and Oscoda to your list.  And Lake County's only connection is via the Badger as noted above for Midland.
Title: Re: Counties with NO Direct Routes to Other States
Post by: Flint1979 on April 12, 2020, 09:21:48 AM
Quote from: GaryV on April 12, 2020, 08:22:10 AM
Quote from: Flint1979 on April 11, 2020, 08:03:14 PM
Michigan has some. I know in my area that Gladwin, Midland, Tuscola, Sanillac and Huron don't have any routes that connect to another state. That's just a start for Michigan. My county has I-75 and US-23 that connect to Ohio and I-75 to Ontario, Canada.
You aren't counting the Badger as part of US-10?  That would eliminate Midland.

In the UP, I see only Luce County not having a single State/US/Interstate highway connection to another state.  Although if I recall correctly, at one time M-28 was concurrent with US-2 into Wisconsin, so historically it would not have qualified.

In the Lower Peninsula I add Montmorency and Oscoda to your list.  And Lake County's only connection is via the Badger as noted above for Midland.
You are correct however I have a hard time considering Lake Michigan as being a part of the route but it is. There is probably a few more. Leelanau and Alger seem like they could make the list as well. I'm thinking off the top of my head and not looking at a map. The way I'm thinking is the counties that  I-75, US-24, US-23, US-127, I-69, US-131, US-31, US-12, I-94, US-41, US-141, US-2, US-8 or US-45 don't go through. I can't think of another highway that leaves the state.

Another thing are we counting state highways that obviously end at the state line? Like Ionia County could count but M-66 goes to the Indiana State line.
Title: Re: Counties with NO Direct Routes to Other States
Post by: NWI_Irish96 on April 12, 2020, 09:27:58 AM
Quote from: Flint1979 on April 12, 2020, 09:21:48 AM
Quote from: GaryV on April 12, 2020, 08:22:10 AM
Quote from: Flint1979 on April 11, 2020, 08:03:14 PM
Michigan has some. I know in my area that Gladwin, Midland, Tuscola, Sanillac and Huron don't have any routes that connect to another state. That's just a start for Michigan. My county has I-75 and US-23 that connect to Ohio and I-75 to Ontario, Canada.
You aren't counting the Badger as part of US-10?  That would eliminate Midland.

In the UP, I see only Luce County not having a single State/US/Interstate highway connection to another state.  Although if I recall correctly, at one time M-28 was concurrent with US-2 into Wisconsin, so historically it would not have qualified.

In the Lower Peninsula I add Montmorency and Oscoda to your list.  And Lake County's only connection is via the Badger as noted above for Midland.
You are correct however I have a hard time considering Lake Michigan as being a part of the route but it is. There is probably a few more. Leelanau and Alger seem like they could make the list as well. I'm thinking off the top of my head and not looking at a map. The way I'm thinking is the counties that  I-75, US-24, US-23, US-127, I-69, US-131, US-31, US-12, I-94, US-41, US-141, US-2, US-8 or US-45 don't go through. I can't think of another highway that leaves the state.

Another thing are we counting state highways that obviously end at the state line? Like Ionia County could count but M-66 goes to the Indiana State line.


Although the distinction is really arbitrary, the consensus seems to be that if a state route maintains the same route number in a neighboring state, it qualifies as a continuous route.
Title: Re: Counties with NO Direct Routes to Other States
Post by: Flint1979 on April 12, 2020, 10:01:27 AM
Quote from: cabiness42 on April 12, 2020, 09:27:58 AM
Quote from: Flint1979 on April 12, 2020, 09:21:48 AM
Quote from: GaryV on April 12, 2020, 08:22:10 AM
Quote from: Flint1979 on April 11, 2020, 08:03:14 PM
Michigan has some. I know in my area that Gladwin, Midland, Tuscola, Sanillac and Huron don't have any routes that connect to another state. That's just a start for Michigan. My county has I-75 and US-23 that connect to Ohio and I-75 to Ontario, Canada.
You aren't counting the Badger as part of US-10?  That would eliminate Midland.

In the UP, I see only Luce County not having a single State/US/Interstate highway connection to another state.  Although if I recall correctly, at one time M-28 was concurrent with US-2 into Wisconsin, so historically it would not have qualified.

In the Lower Peninsula I add Montmorency and Oscoda to your list.  And Lake County's only connection is via the Badger as noted above for Midland.
You are correct however I have a hard time considering Lake Michigan as being a part of the route but it is. There is probably a few more. Leelanau and Alger seem like they could make the list as well. I'm thinking off the top of my head and not looking at a map. The way I'm thinking is the counties that  I-75, US-24, US-23, US-127, I-69, US-131, US-31, US-12, I-94, US-41, US-141, US-2, US-8 or US-45 don't go through. I can't think of another highway that leaves the state.

Another thing are we counting state highways that obviously end at the state line? Like Ionia County could count but M-66 goes to the Indiana State line.


Although the distinction is really arbitrary, the consensus seems to be that if a state route maintains the same route number in a neighboring state, it qualifies as a continuous route.
So M-66 wouldn't count in this example since it becomes Indiana SR-9 at the state line. Indiana wouldn't have SR-66 in that location though since their state highways follow the same grid the US highway system uses.
Title: Re: Counties with NO Direct Routes to Other States
Post by: Flint1979 on April 12, 2020, 10:44:31 AM
Nevermind on Alger County I didn't realize it goes as far west as it does to include US-41 in it's southwest corner.
Title: Re: Counties with NO Direct Routes to Other States
Post by: GaryV on April 12, 2020, 11:47:17 AM
Quote from: Flint1979 on April 12, 2020, 09:21:48 AM
Quote from: GaryV on April 12, 2020, 08:22:10 AM
Quote from: Flint1979 on April 11, 2020, 08:03:14 PM
Michigan has some. I know in my area that Gladwin, Midland, Tuscola, Sanillac and Huron don't have any routes that connect to another state. That's just a start for Michigan. My county has I-75 and US-23 that connect to Ohio and I-75 to Ontario, Canada.
You aren't counting the Badger as part of US-10?  That would eliminate Midland.

In the UP, I see only Luce County not having a single State/US/Interstate highway connection to another state.  Although if I recall correctly, at one time M-28 was concurrent with US-2 into Wisconsin, so historically it would not have qualified.

In the Lower Peninsula I add Montmorency and Oscoda to your list.  And Lake County's only connection is via the Badger as noted above for Midland.
You are correct however I have a hard time considering Lake Michigan as being a part of the route but it is. There is probably a few more. Leelanau and Alger seem like they could make the list as well. I'm thinking off the top of my head and not looking at a map. The way I'm thinking is the counties that  I-75, US-24, US-23, US-127, I-69, US-131, US-31, US-12, I-94, US-41, US-141, US-2, US-8 or US-45 don't go through. I can't think of another highway that leaves the state.

Another thing are we counting state highways that obviously end at the state line? Like Ionia County could count but M-66 goes to the Indiana State line.

You're right, Leelanau should be included in the list.

If you don't count M highways that become another number as they cross to IN, we would add Cass County to the list, even though it borders IN.  Hillsdale or Lenawee would be candidates, except that US-127 runs right down the border between the counties, and so is in both of them continuing into OH.

Other counties with the only connection as M-66 are Barry and Missaukee.
Title: Re: Counties with NO Direct Routes to Other States
Post by: Flint1979 on April 12, 2020, 12:00:20 PM


Quote from: GaryV on April 12, 2020, 11:47:17 AM
Quote from: Flint1979 on April 12, 2020, 09:21:48 AM
Quote from: GaryV on April 12, 2020, 08:22:10 AM
Quote from: Flint1979 on April 11, 2020, 08:03:14 PM
Michigan has some. I know in my area that Gladwin, Midland, Tuscola, Sanillac and Huron don't have any routes that connect to another state. That's just a start for Michigan. My county has I-75 and US-23 that connect to Ohio and I-75 to Ontario, Canada.
You aren't counting the Badger as part of US-10?  That would eliminate Midland.

In the UP, I see only Luce County not having a single State/US/Interstate highway connection to another state.  Although if I recall correctly, at one time M-28 was concurrent with US-2 into Wisconsin, so historically it would not have qualified.

In the Lower Peninsula I add Montmorency and Oscoda to your list.  And Lake County's only connection is via the Badger as noted above for Midland.
You are correct however I have a hard time considering Lake Michigan as being a part of the route but it is. There is probably a few more. Leelanau and Alger seem like they could make the list as well. I'm thinking off the top of my head and not looking at a map. The way I'm thinking is the counties that  I-75, US-24, US-23, US-127, I-69, US-131, US-31, US-12, I-94, US-41, US-141, US-2, US-8 or US-45 don't go through. I can't think of another highway that leaves the state.

Another thing are we counting state highways that obviously end at the state line? Like Ionia County could count but M-66 goes to the Indiana State line.

You're right, Leelanau should be included in the list.

If you don't count M highways that become another number as they cross to IN, we would add Cass County to the list, even though it borders IN.  Hillsdale or Lenawee would be candidates, except that US-127 runs right down the border between the counties, and so is in both of them continuing into OH.

Other counties with the only connection as M-66 are Barry and Missaukee.

Cass has US-12 in it. I was thinking US-127 entered Missaukee but it misses it by a few miles to the east.
Title: Re: Counties with NO Direct Routes to Other States
Post by: jp the roadgeek on April 12, 2020, 01:17:59 PM
Quote from: Roadgeekteen on April 11, 2020, 05:43:00 PM
Two in Massachusetts. Not surprisingly, they are Dukes county and Nantucket county.

Pretty sure those are the only two in all of New England.
Title: Re: Counties with NO Direct Routes to Other States
Post by: Bitmapped on April 12, 2020, 01:23:07 PM
West Virginia:
- Webster County qualifies. It only has 3 state routes and none of them go to the state line.
- Wirt County qualifies (barely). WV 14 will get you within about 2 blocks of the Ohio state line.
- Tyler County is debatable. An unsigned extension of WV 18 runs to the landing for the Sistersville Ferry, which connects to Ohio.

All of the other counties in West Virginia have either a US route or Interstate.
Title: Re: Counties with NO Direct Routes to Other States
Post by: webny99 on April 12, 2020, 05:26:19 PM
Quote from: jp the roadgeek on April 12, 2020, 01:17:59 PM
Quote from: Roadgeekteen on April 11, 2020, 05:43:00 PM
Two in Massachusetts. Not surprisingly, they are Dukes county and Nantucket county.

Pretty sure those are the only two in all of New England.

Surely there's some in Maine, no?
Title: Re: Counties with NO Direct Routes to Other States
Post by: formulanone on April 12, 2020, 06:29:15 PM
If I'm understanding the thread premise correctly, all of Alabama's 67 counties have a direct connection to another state via Interstate, US route, or a singular state route (Wilcox 10, Clay 48, Geneva...there's several).
Title: Re: Counties with NO Direct Routes to Other States
Post by: Roadgeekteen on April 12, 2020, 06:30:25 PM
Quote from: webny99 on April 12, 2020, 05:26:19 PM
Quote from: jp the roadgeek on April 12, 2020, 01:17:59 PM
Quote from: Roadgeekteen on April 11, 2020, 05:43:00 PM
Two in Massachusetts. Not surprisingly, they are Dukes county and Nantucket county.

Pretty sure those are the only two in all of New England.

Surely there's some in Maine, no?
counties in Maine are pretty big.
Title: Re: Counties with NO Direct Routes to Other States
Post by: sandwalk on April 12, 2020, 06:56:40 PM
I was going to suggest Monroe County, Ohio until I found out State Route 536, while unsigned, becomes West Virginia Route 7 at the New Martinsville Bridge.

That being the case, I believe all counties in Ohio have a direct route connection with another state.
Title: Re: Counties with NO Direct Routes to Other States
Post by: wanderer2575 on April 12, 2020, 07:42:14 PM
Quote from: GaryV on April 12, 2020, 08:22:10 AM
Quote from: Flint1979 on April 11, 2020, 08:03:14 PM
Michigan has some. I know in my area that Gladwin, Midland, Tuscola, Sanillac and Huron don't have any routes that connect to another state. That's just a start for Michigan. My county has I-75 and US-23 that connect to Ohio and I-75 to Ontario, Canada.
You aren't counting the Badger as part of US-10?  That would eliminate Midland.

In the UP, I see only Luce County not having a single State/US/Interstate highway connection to another state.  Although if I recall correctly, at one time M-28 was concurrent with US-2 into Wisconsin, so historically it would not have qualified.

In the Lower Peninsula I add Montmorency and Oscoda to your list.  And Lake County's only connection is via the Badger as noted above for Midland.

Add Leelanau and Newaygo counties to the list for the Lower Peninsula.
Title: Re: Counties with NO Direct Routes to Other States
Post by: Flint1979 on April 13, 2020, 07:20:10 AM
Quote from: wanderer2575 on April 12, 2020, 07:42:14 PM
Quote from: GaryV on April 12, 2020, 08:22:10 AM
Quote from: Flint1979 on April 11, 2020, 08:03:14 PM
Michigan has some. I know in my area that Gladwin, Midland, Tuscola, Sanillac and Huron don't have any routes that connect to another state. That's just a start for Michigan. My county has I-75 and US-23 that connect to Ohio and I-75 to Ontario, Canada.
You aren't counting the Badger as part of US-10?  That would eliminate Midland.

In the UP, I see only Luce County not having a single State/US/Interstate highway connection to another state.  Although if I recall correctly, at one time M-28 was concurrent with US-2 into Wisconsin, so historically it would not have qualified.

In the Lower Peninsula I add Montmorency and Oscoda to your list.  And Lake County's only connection is via the Badger as noted above for Midland.

Add Leelanau and Newaygo counties to the list for the Lower Peninsula.
I had Leelanau but not Newaygo.
Title: Re: Counties with NO Direct Routes to Other States
Post by: CNGL-Leudimin on April 13, 2020, 08:50:10 AM
All counties of Hawaii :bigass:
Title: Re: Counties with NO Direct Routes to Other States
Post by: mrcmc888 on April 13, 2020, 11:56:58 AM
Tennessee, being a crossroads state with plenty of state routes that go border to border (many with unsigned parts) has none, by my estimation.
Title: Re: Counties with NO Direct Routes to Other States
Post by: cpzilliacus on April 13, 2020, 03:52:37 PM
Quote from: webny99 on April 11, 2020, 05:28:03 PM
Quote from: webny99 on April 11, 2020, 05:04:52 PM
I believe some of the remaining counties have zero connections to any other state... which gets me thinking...

... in figuring out which counties in New York are directly connected by numbered route to Pennsylvania, I discovered something interesting. Several of our counties actually have ZERO direct numbered highway connections to any other state.

48 of New York's 62 counties have direct connections to Pennsylvania.
Of the 14 that don't, 9 have direct routes to other bordering states, and a 10th (Hamilton County) has NY 30, a direct route to Quebec.

That leaves just 4 counties, Suffolk, Nassau, Lewis and Orleans*, with no direct routes to anywhere out of state.
How many such counties are there in your state?

Most counties in my state share a border with one of our neighbors, and from Frederick County to Garrett County in the west, all of them border Pennsylvania on the north and Virginia or West Virginia on the south.

I can think of two counties that do not share a land border (or a bridge) to a neighboring state and have no Interstate or U.S. highway miles.  Those are Calvert County and St. Mary's County.  But those fail the "direct highway" test, since both are connected to the District of Columbia (which I consider to be a state in this context) by MD-4.  Additionally, St. Mary's County has a second direct route to D.C. in MD-5, which runs the length of St. Mary's, from the southern tip of Maryland's Western Shore of the Chesapeake Bay at Point Lookout all the way to D.C. (both MD-5 and MD-4 end at the D.C./Maryland border).

County-equivalent Baltimore City does not border any other state, but has three Interstate highways that lead directly to neighboring states (in addition to U.S. 1 and U.S. 40), so it does not count.

So the answer for Maryland is zero. 
Title: Re: Counties with NO Direct Routes to Other States
Post by: GaryA on April 13, 2020, 04:38:07 PM
Quote from: TheStranger on April 11, 2020, 09:46:10 PM
In California, Trinity County used to be this, but when State Route 299 (supplanting the former US 299) was extended to connect to a dirt road in Nevada, it no longer counts.

Lake County however does (Route 29, 175, 20, 53 all do not lead to a state border).

Butte County looks like it does now (state route 99, 70, 149, 191, 32, 162); prior to 1964 however 99 was US 99E and 70 at the time was Alternate US 40, the latter of which did cross into Nevada and the former of which was part of the multi-state US 99.

Because of the 1964 decommissioning of US 99E and Alternate US 40, Yuba County now also fits this category (99, 65, 70, 49, 20).

Tulare County fits this category specifically because the two segments of Route 190 have never been joined together.  Madera County fits due to US 99 becoming Route 99.

Mariposa County and Tuolumne County qualify as Route 120 ends at US 6 just a few miles from the Nevada state line.

Calaveras County also seems to be in this category.

For California, Santa Cruz County seems to also be in this category (routes 1, 9, 17, 35, 129, 152, 236).
Title: Re: Counties with NO Direct Routes to Other States
Post by: CoreySamson on April 13, 2020, 04:55:56 PM
Texas has at least one, Delta County.

However, I'm surprised Brazoria County actually has a direct route to Oklahoma via TX 6.
Title: Re: Counties with NO Direct Routes to Other States
Post by: formulanone on April 14, 2020, 12:14:03 PM
Florida only has one county without a singular route designation to another state, and that's Liberty County. After FL 65 was truncated north of US 90 near Quincy (as CR 65), it's had no directly-numbered route to any other state.
Title: Re: Counties with NO Direct Routes to Other States
Post by: paulthemapguy on April 14, 2020, 08:59:59 PM
I figured out Illinois.  Jasper and Menard Counties both count.  Calhoun County probably also counts, even though it has a ferry to Winfield, Missouri.  That ferry isn't along a state or other kind of route, though. To figure this out, I made a big list of every county and trying to name a connecting route from each one, starting with naming all 102 counties from memory  :D
Title: Re: Counties with NO Direct Routes to Other States
Post by: mrcmc888 on April 14, 2020, 09:06:06 PM
Quote from: formulanone on April 14, 2020, 12:14:03 PM
Florida only has one county without a singular route designation to another state, and that's Liberty County. After FL 65 was truncated north of US 90 near Quincy (as CR 65), it's had no directly-numbered route to any other state.

Looking on Google Maps it appears that a small sliver of FL-267, which runs to the Georgia border, does enter Liberty County.
Title: Re: Counties with NO Direct Routes to Other States
Post by: roadfro on April 19, 2020, 12:49:23 PM
Quote from: gonealookin on April 11, 2020, 07:58:33 PM
Since all of Nevada's 16 counties plus the independent city of Carson City are served by either a US highway or an interstate that crosses into another state, there aren't any here.

Technically true.

Functionally, though, you could consider Storey County for this list. I-80 only very briefly passes through the northern tip of Storey County where there is no access between I-80 and the rest of the county. So someone living/working in Storey County can't take get out of the state by use of a single route.


Quote from: webny99 on April 11, 2020, 09:59:48 PM
Quote from: TheStranger on April 11, 2020, 09:46:10 PM
In California, Trinity County used to be this, but when State Route 299 (supplanting the former US 299) was extended to connect to a dirt road in Nevada, it no longer counts.

Well, as long as the dirt road is at least a numbered state highway. If it's less than that, I would say the county still counts.

That dirt road is the northernmost section of the pre-1976 Nevada State Route 8A, and is no longer state-maintained. The old route, to my knowledge, is not numbered by Washoe County (and likely receives minimal, if any, maintenance from the county as it is in the sparsely-populated northwestern corner of the state).
Title: Re: Counties with NO Direct Routes to Other States
Post by: formulanone on April 19, 2020, 01:08:32 PM
Quote from: mrcmc888 on April 14, 2020, 09:06:06 PM
Quote from: formulanone on April 14, 2020, 12:14:03 PM
Florida only has one county without a singular route designation to another state, and that's Liberty County. After FL 65 was truncated north of US 90 near Quincy (as CR 65), it's had no directly-numbered route to any other state.

Looking on Google Maps it appears that a small sliver of FL-267, which runs to the Georgia border, does enter Liberty County.

Yeah, you're right about that. 267 just crossed the plane of Liberty County line at FL 20!
Title: Re: Counties with NO Direct Routes to Other States
Post by: JayhawkCO on April 19, 2020, 09:48:42 PM
A few in Colorado: Gilpin, Hinsdale, Custer, and San Miguel.  San Miguel is on the Utah border as well, but doesn't have any numbered routes that cross the border, which may be unique in the country I suppose.  Any others that are on a border but don't have a road that eventually crosses one?

Chris
Title: Re: Counties with NO Direct Routes to Other States
Post by: index on April 20, 2020, 05:35:10 AM
With only a handful of state highways, 306, 304, 55, and a tiny slice of 33, it doesn't appear Pamlico County, NC has any direct connection to another state. I don't believe Hyde has any direct connections either (US 264 doesn't leave the state), and some other rural eastern NC counties like Chowan and Tyrrell would have no direct connections if it wasn't for US 17 and 64. Western North Carolina, while rural, is on the border with Tennessee so its counties also avoid this situation.

Correct me if I'm wrong but I don't think any SC county has this situation at all, I think all of them have at least two US highways and there aren't any intra-state ones there.