Not sure if there is a shorter name for this phenomenon-but these are highways that run through a portion of a state that is completely isolated from the rest of the state-i.e. you must go through an adjoining state to reach the rest of the state by road. The longest example of this would probably be I-15 in Arizona. Another would be I-684 which goes through a small portion of Connecticut. US 212 does this twice-in the northeast corner of Wyoming and again in Montana just NE of Yellowstone NP. Another one I know of is IA 165 in Carter Lake, IA-which is part of the road between downtown Omaha and Eppley Airfield. Other examples?
there are some loops of the Alaska Highway that alternate between British Columbia and Yukon that share this property.
also, the town of Hyder, Alaska, can be reached only from Stewart, BC.
US-191 also does it north of West Yellowstone, Montana- it enters Wyoming for a few miles. Montana maintains the road though.
WYO 70 dips southward into CO to pass through the town of Slater and it is maintained by WyDOT.
ME 113 enters New Hampshire twice and both are maintained by NHDOT. NHDOT even signs ME 113 with Maine's square. There is even a spur off of it, NH 113B, in Chatham.
I know it doesn't strictly count, but CA-266 can only be accessed via CA-168. And the route itself is really just a connector between two Nevada State Routes.
Quote from: agentsteel53 on November 13, 2010, 01:04:12 AM
there are some loops of the Alaska Highway that alternate between British Columbia and Yukon that share this property.
also, the town of Hyder, Alaska, can be reached only from Stewart, BC.
AK 7 may be the big fish for this.
Also, one I'm not 100% certain about, but it seems that NT 5 dips into Alberta a couple times, with its final portion in Fort Smith just a couple feet south of the 60° line (which would be in Alberta).
State Rt 896 crosses into Maryland for a very short piece between PA 896 and DE 896...I don't remember if there is a side road intersection in Maryland. Also, the I-84 bridge over the Delaware River bet PA and NY I believe barely touches NJ.
Also I-95 and I-495 briefly pass through DC on the Woodrow Wilson Bridge.
Isn't I-24 in Georgia for less than half a mile and uses Tennessee's mile markers?
MN-23 briefly enters Wisconsin just south of Duluth:
http://maps.google.com/maps?q=duluth,+mn&oe=utf-8&client=firefox-a&ie=UTF8&hq=&hnear=Duluth,+St+Louis,+Minnesota&gl=us&ei=jDLgTLqvDIjqnQfpkbi8CA&ved=0CB0Q8gEwAA&ll=46.656977,-92.288246&spn=0.125363,0.285988&t=h&z=12
Quote from: Quillz on November 14, 2010, 01:51:24 PM
Isn't I-24 in Georgia for less than half a mile and uses Tennessee's mile markers?
I-24 is in Georgia for 4.1 miles & has an interchange with I-59 in Georgia.
Quote from: Grzrd on November 14, 2010, 02:07:47 PM
Quote from: Quillz on November 14, 2010, 01:51:24 PM
Isn't I-24 in Georgia for less than half a mile and uses Tennessee's mile markers?
I-24 is in Georgia for 4.1 miles & has an interchange with I-59 in Georgia.
There's also an exit that connects to US 11 in Georgia, but they both keep Tennesse's exit numbering.
That exit serves GA 299 (Exit 169). It's a good exit to stop at if you're just going to Chattanooga as gas prices are generally cheaper in GA than in TN.
Quote from: jemacedo9 on November 14, 2010, 10:45:59 AM
Also, the I-84 bridge over the Delaware River bet PA and NY I believe barely touches NJ.
No. The state tripoint marker is in the shadow of the bridge, but is definitely south of it. Oscar Voss took a picture of me sitting on the marker and i was looking toward the bridge.
Point Roberts, WA, can only be accessed (via land) through Canada. This includes the unnumbered roads that are located there.
QC-199 is only accessible by boat... from Prince Edward's Island.
(Well, there seems to be a Montreal ferry too on Google Maps, but I never heard anyone talk about it and I can't imagine the price...)
http://en.wikipedia.org/wiki/Quebec_Route_199
Quote from: jemacedo9 on November 14, 2010, 10:45:59 AM
State Rt 896 crosses into Maryland for a very short piece between PA 896 and DE 896...I don't remember if there is a side road intersection in Maryland.
There is, it's called Little Egypt Road.
Also, just over the line in Pennsylvania, there's a turnoff called Elbow Lane that stays very close to the Pennsylvania/Maryland line.
Quote from: Quillz on November 15, 2010, 12:23:14 AM
Point Roberts, WA, can only be accessed (via land) through Canada. This includes the unnumbered roads that are located there.
The same is true of the Northwest Angle in Minnesota, but there are no highways located there.
N54, Ireland (http://maps.google.com/?ie=UTF8&ll=54.143233,-7.296124&spn=0.081448,0.154324&z=13) - the road here keeps on changing between N54 (in the Republic) and A3 (in Northern Ireland). While other sections of N54 and A3 in the borer wiggle have routes that link them back to the main road network of the country, this one doesn't.
here (http://maps.google.com/?ie=UTF8&ll=52.530425,-3.106213&spn=0.084587,0.219727&z=13)'s something similar in England, where you have to drive through Wales to get there. A bit different, given the road numbers are the same.
Quote from: Coelacanth on November 15, 2010, 11:30:51 AM
Quote from: Quillz on November 15, 2010, 12:23:14 AM
Point Roberts, WA, can only be accessed (via land) through Canada. This includes the unnumbered roads that are located there.
The same is true of the Northwest Angle in Minnesota, but there are no highways located there.
There are numbered county highways there. I plan to clinch a couple.
Quote from: signalman on November 14, 2010, 07:14:03 PM
Quote from: Grzrd on November 14, 2010, 02:07:47 PM
Quote from: Quillz on November 14, 2010, 01:51:24 PM
Isn't I-24 in Georgia for less than half a mile and uses Tennessee's mile markers?
I-24 is in Georgia for 4.1 miles & has an interchange with I-59 in Georgia.
There's also an exit that connects to US 11 in Georgia, but they both keep Tennesse's exit numbering.
I drove through there about a year ago and think I made a mental note that the section uses Georgia mileage markers but the exit numbers follow what would have been Tennessee mileage. Don't know if my mind is playing tricks on me. Can anyone confirm or deny?
Quote from: Grzrd on November 16, 2010, 07:54:46 AM
Quote from: signalman on November 14, 2010, 07:14:03 PM
Quote from: Grzrd on November 14, 2010, 02:07:47 PM
Quote from: Quillz on November 14, 2010, 01:51:24 PM
Isn't I-24 in Georgia for less than half a mile and uses Tennessee's mile markers?
I-24 is in Georgia for 4.1 miles & has an interchange with I-59 in Georgia.
There's also an exit that connects to US 11 in Georgia, but they both keep Tennesse's exit numbering.
I drove through there about a year ago and think I made a mental note that the section uses Georgia mileage markers but the exit numbers follow what would have been Tennessee mileage. Don't know if my mind is playing tricks on me. Can anyone confirm or deny?
You got it right. Georgia mile markers, would-be Tennessee exit numbers.
Quote from: topay on November 16, 2010, 08:47:08 AM
You got it right. Georgia mile markers, would-be Tennessee exit numbers.
I know I'm straying waaaaay off topic, but does this situation exist anywhere else on interstate system, i.e. mile markers reflect "home" state mileage, but exit numbers correspond to neighboring state's "would-be" mileage?
Quote from: Grzrd on November 16, 2010, 09:05:27 AM
Quote from: topay on November 16, 2010, 08:47:08 AM
You got it right. Georgia mile markers, would-be Tennessee exit numbers.
I know I'm straying waaaaay off topic, but does this situation exist anywhere else on interstate system, i.e. mile markers reflect "home" state mileage, but exit numbers correspond to neighboring state's "would-be" mileage?
I 275 around Cincinnati uses exit numbers numbered based on mileage from the I 71/75 interchange, but each state uses its own mile markers.
Quote from: Grzrd on November 16, 2010, 09:05:27 AM
Quote from: topay on November 16, 2010, 08:47:08 AM
You got it right. Georgia mile markers, would-be Tennessee exit numbers.
I know I'm straying waaaaay off topic, but does this situation exist anywhere else on interstate system, i.e. mile markers reflect "home" state mileage, but exit numbers correspond to neighboring state's "would-be" mileage?
NY-17 (future I-86) briefly passes into Pennsylvania but is still maintained by NYDOT. No idea if it actually has any exits on the very brief alignment, though.
Also, CA-161 (really getting off-topic here, sorry) is very close to the Oregon border, but I'm not sure if it actually touches it or not.
Exit 60 for US 220 is entirely in Pennsylvania.
Exit 61 for NY 34/PA 199 has most of the eastbound ramps in PA.
http://maps.google.com/maps?f=q&source=s_q&hl=en&geocode=&q=Waverly,+NY&sll=37.0625,-95.677068&sspn=50.244827,51.591797&ie=UTF8&hq=&hnear=Waverly,+Tioga,+New+York&ll=41.999655,-76.537113&spn=0.023218,0.025191&t=h&z=15
I have no idea whose mileposts are used.
NY 120A, which runs along the NY/CT border, veers completely into CT for a bit...but is still maintained by NYSDOT.
Quote from: mightyace on November 16, 2010, 02:25:38 PM
Exit 60 for US 220 is entirely in Pennsylvania.
Exit 61 for NY 34/PA 199 has most of the eastbound ramps in PA.
http://maps.google.com/maps?f=q&source=s_q&hl=en&geocode=&q=Waverly,+NY&sll=37.0625,-95.677068&sspn=50.244827,51.591797&ie=UTF8&hq=&hnear=Waverly,+Tioga,+New+York&ll=41.999655,-76.537113&spn=0.023218,0.025191&t=h&z=15
I have no idea whose mileposts are used.
I would assume NY's, given that it's maintained by NYSDOT.
^^^
I would think so, too. But, it's been over 25 years since I've been on that stretch of highway and I don't care to take the time to slug through Google streetview.
These exits may be the last exits in PA with sequential numbering.
Quote from: SidS1045 on November 16, 2010, 09:05:45 PM
NY 120A, which runs along the NY/CT border, veers completely into CT for a bit...but is still maintained by NYSDOT.
It makes no less than four crossings of the state line (six southbound, if Google Maps is accurate), one of which involves a significant length straddling it. It intersects with CT 15 while straddling, so the southern of its two ventures into Connecticut isn't isolated. But the northern one is.
Re. the purported Md. 896: I once drove 896 between Newark and some place in Pennsylvania to see if it was marked in Maryland. It was not. This was probably over 15 years ago, so if someone knows it's changed, please feel free to say so.
And I think I-684 in Connecticut is a special degree of isolation in that you can't get off (or on to) it in Connecticut. Which takes it beyond roads like, um, not(?)-Md.-896 in not having any intersections with even unnumbered roads in the state. If you know what I mean.
(The 2009-2010 Maryland official road map shows Del. and Pa. 896, but not Md. 896. By which I mean they have oval 896 markers in Delaware and Pennsylvania but no rectangle-with-a-top-part 896 marker in Maryland.)
Quote from: Michael in Philly on November 23, 2010, 07:02:27 PM
Re. the purported Md. 896: I once drove 896 between Newark and some place in Pennsylvania to see if it was marked in Maryland. It was not. This was probably over 15 years ago, so if someone knows it's changed, please feel free to say so.
(The 2009-2010 Maryland official road map shows Del. and Pa. 896, but not Md. 896. By which I mean they have oval 896 markers in Delaware and Pennsylvania but no rectangle-with-a-top-part 896 marker in Maryland.)
I want to say that they did have a Maryland reassurance when I crossed the border, but it may have just been Welcome to Maryland. Either way, it's definitely MD 896.
I take that back. No trace of welcome or reassurance signage according to Google.
I-684 in CT cannot be accessed from within CT, you have to go into NY to get on it.
Quote from: Quillz on November 16, 2010, 01:23:48 PMAlso, CA-161 (really getting off-topic here, sorry) is very close to the Oregon border, but I'm not sure if it actually touches it or not.
I believe it straddles the actual border, but I was not able to find monumentation to prove it when I travelled its entire length in 2003. (I don't consider pavement joints or the location of welcome signage to be reliable evidence. At the US 50 crossing of the Kansas-Colorado border, for example, Colorado has made a naked land grab and put the Prower County line sign, done to CDOT standards for the signface design and on a typical CDOT slip base, on the Kansas side.)
Quote from: PennDOTFan on November 13, 2010, 05:35:38 PM
ME 113 enters New Hampshire twice and both are maintained by NHDOT. NHDOT even signs ME 113 with Maine's square. There is even a spur off of it, NH 113B, in Chatham.
Damn you, you beat me to it! :-D
So how about NB774 (http://maps.google.com/?ll=44.888,-66.939&z=12)? There are ferries, but no roads to the rest of New Brunswick without taking the bridge into the United States.
Quote from: huskeroadgeek on November 13, 2010, 01:00:35 AM
Not sure if there is a shorter name for this phenomenon-but these are highways that run through a portion of a state that is completely isolated from the rest of the state-i.e. you must go through an adjoining state to reach the rest of the state by road. The longest example of this would probably be I-15 in Arizona. Another would be I-684 which goes through a small portion of Connecticut. US 212 does this twice-in the northeast corner of Wyoming and again in Montana just NE of Yellowstone NP. Another one I know of is IA 165 in Carter Lake, IA-which is part of the road between downtown Omaha and Eppley Airfield. Other examples?
Quote from: huskeroadgeek on November 13, 2010, 01:00:35 AM
Not sure if there is a shorter name for this phenomenon-but these are highways that run through a portion of a state that is completely isolated from the rest of the state-i.e. you must go through an adjoining state to reach the rest of the state by road. The longest example of this would probably be I-15 in Arizona. Another would be I-684 which goes through a small portion of Connecticut. US 212 does this twice-in the northeast corner of Wyoming and again in Montana just NE of Yellowstone NP. Another one I know of is IA 165 in Carter Lake, IA-which is part of the road between downtown Omaha and Eppley Airfield. Other examples?
SR2 in Baker and Coumbia County FL you have to enter GA or use county roads to reach another state highway... not quite haveing to enter another state
The route leading into Kentucky Bend in far western Kentucky (an extension of TN 22) once upon a time carried a state route number, KY 313. It is shown on the 1973 and 1976 official state highway maps (which are available online). By 1983, it was no longer a state highway (and had been paved). It had been decommissioned by 1981, when the official orders were posted.
West Virginia state highway 102 in Mercer County touches no other state highways, and begins and ends at the Virginia state line.
Quote from: Andrew T. on November 28, 2010, 01:58:42 PM
West Virginia state highway 102 in Mercer County touches no other state highways, and begins and ends at the Virginia state line.
If I'm not mistaken there is at least one "county" highway -- actually maintained by the state -- that connects WV 102 to US 52.
I feel like CA-186 is eligible. About a mile long or so, only touches I-8 and it's entire purpose is to serve a little-used border crossing near Winterhaven.