We have AZ, UT, CO, and NM all common to four state corners which is the only place in the US that has happened.
In Florida we have three locations where 4 corners meet.
1) Lake, Orange, Osceola, and Polk meet near the intersection of US 27 and US 192.
2) Hillsborough, Polk, Hardee, and Manatee meet on FL 37 SE of Tampa.
3) DeSoto, Highlands, Glades, and Charlotte Counties in a rural area with no roads east of Punta Gorda, FL.
Any other situations?
Indiana:
1) Starke, Marshall, Pulaski, Fulton
2) Porter, LaPorte, Jasper, Starke
Starke County is part of two 4 corner points.
In Maryland, Frederick Montgomery Carroll & Howard counties meet at Parr's Spring (the source of the South Branch Patapsco River), just south of I-70 exit 68 in Mt. Airy.
Kansas has a few of these.
My own county of Sedgwick has a four-corners with Sumner, Cowley, and Butler.
I grew up not too far from one in Northern IL: DuPage, Kane, Will, and Kendall 4-corner in Aurora
Lake, McHenry, Cook, and Kane get close, but I think they just miss
Winnebago, Boone, DeKalb, and Ogle
Central IL has Vermilion, Champaign, Douglas, and Edgar
And I'm not too awful far from one in Southern IL: Gallatin, Saline, White, and Hamilton
Oklahoma has only one: Grant-Kay-Garfield-Noble.
There's dozens of them in IA and TX.
Michigan has a lot:
Van Buren-Cass-St. Joseph-Kalamazoo
Kalamazoo-St. Joseph-Branch-Calhoun
Montcalm-Ionia-Clinton-Gratiot
Mason-Oceana-Newaygo-Lake
Lake-Newaygo-Mecosta-Osceola
Ocesola-Mecosta-Isabella-Clare
Clare-Isabella-Midland-Gladwin
Benzie-Manistee-Wexford-Grand Traverse
Grand Traverse-Wexford-Missaukee-Kalkaska
Kalkaska-Missaukee-Roscommon-Crawford
Crawford-Roscommon-Ogemaw-Oscoda
Oscoda-Ogemaw-Iosco-Alcona
Antrim-Kalkaska-Crawford-Otsego
Otsego-Crawford-Oscoda-Montmorency
Montmorency-Oscoda-Alcona-Alpena
There are a few near-misses, such as Gratiot-Clinton-Shiawassee-Saginaw (Gratiot County and Shiawassee County have a short border) and Ingham-Jackson-Washtenaw-Livingston (Jackson County and Livingston County have a very short border)
Quote from: cabiness42 on August 11, 2020, 04:37:45 PM
Indiana:
1) Starke, Marshall, Pulaski, Fulton
2) Porter, LaPorte, Jasper, Starke
Starke County is part of two 4 corner points.
3) DeKalb, LaGrange, Noble, Steuben
Five counties meet in Lake Okeechobee: Glades, Hendry, Palm Beach, Martin, and Okeechobee County.
(https://www.aaroads.com/forum/proxy.php?request=http%3A%2F%2Fedr.state.fl.us%2FContent%2Farea-profiles%2Fcounty%2Fcnty1.png&hash=49accf3f16d62df93fd0d43feb104d7d7be60b00)
Turns out that the State of Florida had to intervene in 1963, as Palm Beach County claimed all of it (https://discover.pbcgov.org/Pages/pbc_facts.aspx). Thus, the oddball quintipoint with limited accessibility.
California - given the squiggly nature of our county lines, there's not many (although several come close)
Santa Clara-Alameda-San Joaquin-Stanislaus
Tuolumne-Mariposa-Stanislaus-Merced
edit: both of these are close but not quite:
San Luis Obispo-Santa Barbara-Ventura-Kern
Monterey-Kings-San Luis Obispo-Kern
Quote from: I-55 on August 11, 2020, 06:37:39 PM
Quote from: cabiness42 on August 11, 2020, 04:37:45 PM
Indiana:
1) Starke, Marshall, Pulaski, Fulton
2) Porter, LaPorte, Jasper, Starke
Starke County is part of two 4 corner points.
3) DeKalb, LaGrange, Noble, Steuben
Thank you. I was thinking when I was posting it that I was missing one.
Texas has a block of them in the Panhandle, the counties along I-40, the row to the south, and the two rows to the north (12). There's a block of three rows five counties long around Lubbock (10). There's another block from Gaines and Andrews Counties east to Abilene (excluding Gaines and Andrews, because they meet Dawson and Martin at two three-corners) (4). There's one set in Midland and the three counties south and east (1). There's a set from Wichita Falls two wide and three high (2).
I count 29 quadpoints involving 58 counties.
Ohio has two "4-corners"
NE version: Cuyahoga, Geauga, Portage, Summit (near the old Geauga Lake & Sea World complex)
NW version: Henry, Wood, Hancock, Putnam
Utah has two fully within its borders:
- Box Elder-Weber-Tooele-Davis, in the middle of the Great Salt Lake
- Emery-Grand-Wayne-San Juan, along the Green River
In addition to the aforementioned Four Corners, there are two more that also involve a state line:
- Franklin ID-Bear Lake ID-Cache UT-Rich UT
- Grand UT-Mesa CO-San Juan UT-Montrose CO
And then there are a whole bunch of near-misses, some much closer than others:
- Salt Lake-Summit-Utah-Wasatch
- Summit-Daggett-Duchesne-Uintah
- Carbon-Uintah-Emery-Grand (very close to being a true quadripoint)
- Millard-Sevier-Beaver-Piute
- Beaver-Piute-Iron-Garfield
- Oneida ID-Franklin ID-Box Elder UT-Cache UT
- Uinta WY-Sweetwater WY-Summit UT-Daggett UT
None in Massachusetts.
Arkansas has two, both involving Howard County: Howard-Pike-Montgomery-Polk bordering the Ouachita National Forest, and Howard-Hempstead-Little River-Sevier in the middle of Millwood Lake.
I am surprised at how few there are in Wisconsin compared to Michigan, given that they are both laid out in townships based on the Northwest Ordinance. Many of Michigan's counties are in level tiers across the LP.
There's probably places in MI (as noted by @ftballfan) that were intended to be 4-corners, but just miss due to surveying.
I see the Four Corners has been mentioned by the OP, but not their constituent counties: San Juan UT & NM, Montezuma CO and Apache AZ.
I once found out that among the comarcas of Aragon, Spain there is a 4 corners also involving a provincial border: Ribera Baja del Ebro and Bajo Aragon Caspe in Zaragoza and Bajo Martin and Bajo Aragon in Teruel.
PA has a regular one: Warren, Forest, McKean, Elk
And an odd two, I think: Clarion, Armstrong, Butler, Venango and Butler, Armstrong, Westmoreland, Allegheny
And a close call with: Centre, Blair, Cambria, Clearfield
Quote from: kphoger on August 11, 2020, 04:52:01 PM
Kansas has a few of these.
My own county of Sedgwick has a four-corners with Sumner, Cowley, and Butler.
Here are the four-corner ones for Kansas. Unless I've missed something, all of the other apparent ones are actually near misses.
(https://i.imgur.com/vX1pHo1.png)
NJ has none, and it's really not even close.
Delaware doesn't even have 3 counties that connect to each other, since its 3 counties basically divide the state into North/Central/Southern regions.
I've checked the map of NWS county warning areas at Wikipedia (which I once billed as a plan to reform the states :sombrero:)
and there are no 4 corners among them. Scratch that, I've just found one 4 corners of county warning areas in Kansas: NWS Topeka (covering Anderson county), Kansas City/Pleasant Hill (Linn), Wichita (Allen) and Springfield MO (Bourbon). The famous Four Corners is only a tripoint in that respect, as both Montezuma and Utah's San Juan (outside the Glen Canyon National Recreation Area) counties fall under NWS Grand Junction county warning area. Apache county is in NWS Flagstaff, and New Mexico's San Juan county in NWS Albuquerque.
And then there's Etna volcano in Sicily, Italy, where 10 municipalities meet atop it. Looking on a map it appears there are 11 municipalities meeting at that point, but in reality one almost surrounds another (except for that point). There the "four color theorem" fails.
Quote from: kphoger on August 12, 2020, 02:04:57 PM
Quote from: kphoger on August 11, 2020, 04:52:01 PM
Kansas has a few of these.
My own county of Sedgwick has a four-corners with Sumner, Cowley, and Butler.
Here are the four-corner ones for Kansas. Unless I've missed something, all of the other apparent ones are actually near misses.
[snip]
You missed one real 4 corners: that of Woodson/Allen/Wilson/Neosho (If OpenStreetMap is not mistaken). All apparent others can be resolved to two tripoints close to each other even at the furthest out OSM shows county lines, in all cases the county to the southwest borders the one to the northeast.
Iowa has 36 of them (give or take). Of those, the only place I've seen four counties signed at the same time is along IA 17 where Kossuth, Hancock, Wright, and Humboldt counties (https://www.flickr.com/photos/iowahighways/7172741981/) meet.
Off the top of my head, Virginia has one: James City, Newport News (IC), Isle of Wight, Surry.
The counties of Canada's Four Corners:
Keewatin Region (NU), Division No. 23 (MB), Region 5 (NT), Northern Saskatchewan Administration District (SK).
Quote from: CNGL-Leudimin on August 12, 2020, 05:32:59 PM
You missed one real 4 corners: that of Woodson/Allen/Wilson/Neosho (If OpenStreetMap is not mistaken). All apparent others can be resolved to two tripoints close to each other even at the furthest out OSM shows county lines, in all cases the county to the southwest borders the one to the northeast.
You are correct, maestro.
Quote from: kphoger on August 13, 2020, 09:55:00 AM
Quote from: CNGL-Leudimin on August 12, 2020, 05:32:59 PM
You missed one real 4 corners: that of Woodson/Allen/Wilson/Neosho (If OpenStreetMap is not mistaken). All apparent others can be resolved to two tripoints close to each other even at the furthest out OSM shows county lines, in all cases the county to the southwest borders the one to the northeast.
You are correct, maestro.
On Google Earth, it looks like Douglas, Franklin, Miami, and Johnson counties have a true four corner.
Surprisingly, West Virginia appears to have a four corner (Mineral, Grant, Hardy, and Hampshire counties)
Also, Kentucky appears to have one with Bourbon, Montgomery, Bath, and Nicholas counties.
Mississippi has one with Hinds, Rankin, Copiah, and Simpson counties.
One that straddles the NC/SC line: Robeson (NC), Dillon (SC), Horry (SC), Columbus (NC)
Quote from: ftballfan on August 13, 2020, 10:10:42 AM
Quote from: kphoger on August 13, 2020, 09:55:00 AM
Quote from: CNGL-Leudimin on August 12, 2020, 05:32:59 PM
You missed one real 4 corners: that of Woodson/Allen/Wilson/Neosho (If OpenStreetMap is not mistaken). All apparent others can be resolved to two tripoints close to each other even at the furthest out OSM shows county lines, in all cases the county to the southwest borders the one to the northeast.
You are correct, maestro.
On Google Earth, it looks like Douglas, Franklin, Miami, and Johnson counties have a true four corner.
Also correct, sir. That puts Kansas up to 9 four-points.
Quote from: cabiness42 on August 11, 2020, 04:37:45 PM
Indiana:
1) Starke, Marshall, Pulaski, Fulton
2) Porter, LaPorte, Jasper, Starke
Starke County is part of two 4 corner points.
You're first mention was the first one that came to mind even though there are several in Michigan. It's mainly because I still have those four counties to clinch and my plan is to hit the quad point of Starke, Marshall, Pulaski and Fulton counties.
You'll certainly never see it in RI or DE, given that for the most part, counties are stacked south to north. CT is essentially a 4x2 horizontal grid, with plenty of points where 3 (but not 4) counties come together. There is one town in New London County (Colchester) that borders towns in 3 other counties; Marlborough (Hartford), Hebron (Tolland), and East Hampton (Middlesex). Hawaii also has none :sombrero:
Wisconsin has several. Without scouring the entire state, I know that there is one at 124 St/County Line Rd in the City of Milwaukee (Milwaukee/Ozaukee/Washington/Waukesha) and one in the City of Wisconsin Dells (Adams/Columbia/Juneau/Sauk).
Mike
Double checking the NWS county warning area map I found there is actually a junction of 4 forecast areas in Kansas, so I ammended my previous post.
Also, OpenStreetMap verifes that there's indeed another 4 corners in Kansas that I also missed at first glance.
King, Pierce, Yakima and Kittitas Counties converge at Naches Pass, Washington. Accessible only by Forrest Service roads. Open Street Map (https://www.openstreetmap.org/#map=16/47.0870/-121.3730)
Quote from: kphoger on August 12, 2020, 02:04:57 PM
Quote from: kphoger on August 11, 2020, 04:52:01 PM
Kansas has a few of these.
My own county of Sedgwick has a four-corners with Sumner, Cowley, and Butler.
Here are the four-corner ones for Kansas. Unless I've missed something, all of the other apparent ones are actually near misses.
(https://i.imgur.com/vX1pHo1.png)
I like the map you provided. I think you missed two though, what about where Woodson, Allen, Wilson and Neosho come together or is that off by a little bit? Also where Neosho, Wilson, Montgomery and Labette come together. I'm not familiar with Kansas so not sure but just saw those.
Quote from: Flint1979 on August 14, 2020, 10:13:36 AM
what about where Woodson, Allen, Wilson and Neosho come together or is that off by a little bit?
Already pointed out.
Quote from: kphoger on August 13, 2020, 09:55:00 AM
Quote from: CNGL-Leudimin on August 12, 2020, 05:32:59 PM
You missed one real 4 corners: that of Woodson/Allen/Wilson/Neosho (If OpenStreetMap is not mistaken). All apparent others can be resolved to two tripoints close to each other even at the furthest out OSM shows county lines, in all cases the county to the southwest borders the one to the northeast.
You are correct, maestro.
Quote from: Flint1979 on August 14, 2020, 10:13:36 AM
Also where Neosho, Wilson, Montgomery and Labette come together. I'm not familiar with Kansas so not sure but just saw those.
It's a near miss, by about a quarter-mile.
Quote from: kphoger on August 14, 2020, 11:15:07 AM
Quote from: Flint1979 on August 14, 2020, 10:13:36 AM
what about where Woodson, Allen, Wilson and Neosho come together or is that off by a little bit?
Already pointed out.
Quote from: kphoger on August 13, 2020, 09:55:00 AM
Quote from: CNGL-Leudimin on August 12, 2020, 05:32:59 PM
You missed one real 4 corners: that of Woodson/Allen/Wilson/Neosho (If OpenStreetMap is not mistaken). All apparent others can be resolved to two tripoints close to each other even at the furthest out OSM shows county lines, in all cases the county to the southwest borders the one to the northeast.
You are correct, maestro.
Quote from: Flint1979 on August 14, 2020, 10:13:36 AM
Also where Neosho, Wilson, Montgomery and Labette come together. I'm not familiar with Kansas so not sure but just saw those.
It's a near miss, by about a quarter-mile.
There's one that was mentioned earlier by ftballfan which is about 40 miles from my house it's where Saginaw, Clinton, Gratiot and Shiawassee counties come together it's off by about a half mile.
We have three instances here in Mississippi. The first one is the region that involves Copiah, Hinds, Rankin and Simpson counties. Another four-set is in south Mississippi: Hancock, Harrison, Pearl River and Stone. And then there's the complex of 14 counties in eastern and central Mississippi: Attala, Clarke, Holmes, Jasper, Kemper, Lauderdale, Leake, Madison, Neshoba, Newton, Scott, Smith, Winston and Yazoo.
Louisiana has several that are close, but the only one I could find is Allen-Evangeline-Acadia-Jefferson Davis
Unless I'm missing one somewhere, I believe Georgia has four:
Gordon/Pickens/Bartow/Cherokee
Hall/Jackson/Gwinnett/Barrow
Barrow/Jackson/Oconee/Clarke
Twiggs/Wilkinson/Bleckley/Laurens
Quote from: debragga on August 16, 2020, 12:23:42 PM
Louisiana has several that are close, but the only one I could find is Allen-Evangeline-Acadia-Jefferson Davis
Beauregard and Calcasieu parishes almost made the cut with Allen and Jefferson Davis.
Quote from: US 89 on August 16, 2020, 03:50:38 PM
Unless I'm missing one somewhere, I believe Georgia has four:
Gordon/Pickens/Bartow/Cherokee
Hall/Jackson/Gwinnett/Barrow
Barrow/Jackson/Oconee/Clarke
Twiggs/Wilkinson/Bleckley/Laurens
The Hall/Jackson/Gwinnett/Barrow set don't appear to meet at four corners.
Quote from: golden eagle on August 16, 2020, 07:50:02 PM
Quote from: US 89 on August 16, 2020, 03:50:38 PM
Unless I'm missing one somewhere, I believe Georgia has four:
Gordon/Pickens/Bartow/Cherokee
Hall/Jackson/Gwinnett/Barrow
Barrow/Jackson/Oconee/Clarke
Twiggs/Wilkinson/Bleckley/Laurens
The Hall/Jackson/Gwinnett/Barrow set don't appear to meet at four corners.
From county-counting site mob-rule, matching the lines I see on OSM:
(https://i.imgur.com/Y543Y2Y.png)
Google even has a "Four Corners Monument" there, for what it's worth...
Missouri has no four corner county intersections, from what I can tell. It has two close misses, both in the northeast part of the state. They are near-misses by a matter of yards, no more than a eighth of a mile.
-Macon/Shelby/Randolph/Monroe
-Sullivan/Adair/Linn/Macon
Quote from: golden eagle on August 16, 2020, 07:45:51 PM
Quote from: debragga on August 16, 2020, 12:23:42 PM
Louisiana has several that are close, but the only one I could find is Allen-Evangeline-Acadia-Jefferson Davis
Beauregard and Calcasieu parishes almost made the cut with Allen and Jefferson Davis.
Found one where parishes all meet in the middle of Lake Pontchartrain:
St John
St Charles
Jefferson
Tangipahoa
iPhone
Quote from: US 89 on August 16, 2020, 03:50:38 PM
Unless I'm missing one somewhere, I believe Georgia has four:
Gordon/Pickens/Bartow/Cherokee
Hall/Jackson/Gwinnett/Barrow
Barrow/Jackson/Oconee/Clarke
Twiggs/Wilkinson/Bleckley/Laurens
There are a few more in GA, plus two on a state line:
Laurens/Johnson/Emanuel/Treutlen
Treutlen/Emanuel/Montgomery/Toombs
Emanuel/Candler/Tattnall/Toombs
Rabun/Oconee (SC)/Macon (NC)/Jackson (NC)
Brooks/Lowndes/Madison (FL)/Hamilton (FL)
Some more appear to very narrowly miss:
Crawford/Bibb/Peach/Houston
Crawford/Peach/Macon/Taylor
Catoosa/Whitfield/Hamilton (TN)/Bradley (TN)
Seminole/Decatur/Gadsden (FL)/Jackson (FL)
For Colorado, we have the following:
Montezuma, CO; San Juan, NM; Apache, AZ; San Juan, UT - Already listed above
Mesa, CO; Montrose, CO; San Juan, UT; Grand, UT - Already listed above
Dolores, CO; Montezuma, CO; La Plata, CO; San Juan; CO - The only intra-Colorado occurrence, and interestingly the Colorado Trail goes within ~60 feet of it
Chris