In-&-Back Routes (between states, counties, etc.)

[njroadhorse]

NJ 23 flip flops multiple times between Morris and Passaic Counties between Riverdale and Oak Ridge.

I believe I-195 also does this between Monmouth and Ocean Counties.

[WNYroadgeek]

NY 21 near Naples goes into Yates County for a few miles before going back into Ontario County.

[rmsandw]

U.S. 20 & IL 83 in Cook County, IL
IL 123 in Sangamon County, IL
U.S. 51 in Shelby County, IL
Those are the quick few that poped in my head.

Along the same line you have I-80 in IL that WB goes Will, Kendall, then Grundy County, while EB goes Grundy to Will County.  Plus, IL 4 & 13 that SB IL 4/EB IL 13 goes St. Clair to Randolph County, while NB IL 4/WB IL 13 goes Randolph, Washington, then St. Clair County.

[Mr_Northside]

An occasion of an interstate doing this that comes to mind is I-70 - in between Zanesville & Columbus - back & forths between Licking County & Muskingum County.

A non-interstate example that comes to mind is US-219... which bounces back & forth between Jefferson & Clearfield (Pennsylvania) counties a couple of times, starting south of DuBois to Brockway.

[74/171FAN]

I-64 and US 250 enters Goochland County and Louisa County twice NW of Richmond

SR 608 in Prince George County enters Dinwiddie County right before Richard Bland and then quickly reenters Prince George for a short stint before reentering Dinwiddie just south of the Petersburg City Limits

[yakra]

I-95 in Aroostook county ME. Looks like only the NB lanes do this: http://mapper.acme.com/?ll=45.79990,-68.42680&z=14&t=T

[Bickendan]

Northbound I-5 does this with Clackamas and Washington Counties in Oregon. It enters Washington County north of Wilsonville at a north-northwest angle and curves north onto SW 65th Ave, the county line. Northbound reenters Clackamas County; southbound is in Washington County. The county-line straddle continues (on SW 65th Ave) on the Multnomah County side of the Multnomah-Clackamas border until I-5 curves away from Washington County into Portland just south of OR 99W.

[topay]

I-64 and US 250 enters Goochland County and Louisa County twice NW of Richmond

SR 608 in Prince George County enters Dinwiddie County right before Richard Bland and then quickly reenters Prince George for a short stint before reentering Dinwiddie just south of the Petersburg City Limits

What's particularly interesting about I-64/US 250 is that even though they're parallel along that corridor, the sequence of counties is slightly different.  US 250 clips the NW and NE corners of Fluvanna County, giving it an extra "repeat county".

I-64 (from the East)
Henrico
Goochland
Louisa
Goochland
Louisa
Fluvanna
Albemarle

US 250 (from the East)
Henrico
Goochland
Louisa
Goochland
Fluvanna
Louisa
Fluvanna
Albemarle

Another I-64 instance in Virginia is near Williamsburg, where I-64 traverses (from the East):
Newport News
James City County
York County
James City County
New Kent County

And on I-295 around Richmond (clockwise, from I-64 Short Pump):
Henrico County
Hanover County
Henrico County
Chesterfield County

And, although I don't count them, one could argue that Virginia's independent cities allow for repeat counties on all sorts of Interstates, US Routes, and State Routes.

[Bryant5493]

Georgia State Route 212 enters Newton and Jasper counties three times, as it straddles these two county lines. Cities served by this route are Monticello, county seat of Jasper County, and Milledgeville, countyseat of Baldwin County and the former capital of Georgia, from 1806 to 1868. Louisville (pronounced Loo-is-ville) preceded Milledgeville as Georgia's capital (1796 to 1806) and Milledgeville was succeded by the current capital, Atlanta (1868 to present).


Be well,

Bryant

[Scott5114]

Georgia State Route 212 enters Newton and Jasper counties three times

Bizarre...Missouri also has Newton and Jasper counties...Joplin is split between them!

[UptownRoadGeek]

U.S. 90 Business leaving I-10 (Orleans Parish) enters Jefferson Parish briefly over the river and then back into Orleans while still over the river then curves around into Jefferson right after the bridge.

[Marc]

I-40 does this in Carroll County, Tennessee, if I remember correctly.

I-55 does the same for Carroll County, Mississippi too.

[Greybear]

In Arkansas:

I-530 goes from Pulaski Co. to Saline Co. between Exits 9 and 10. It then re-enters Pulaski Co. between Exits 12 and 15.

[Bryant5493]

Georgia State Route 212 enters Newton and Jasper counties three times

Bizarre...Missouri also has Newton and Jasper counties...Joplin is split between them!

Yeah, I found out about S.R. 212's routing through these counties while producing a YouTube video. Another Newton and Jasper counties next to one another... odd.

U.S. 90 Business leaving I-10 (Orleans Parish) enters Jefferson Parish briefly over the river and then back into Orleans while still over the river then curves around into Jefferson right after the bridge.

I forgot about that.


Be well,

Bryant

[TheStranger]

Route 35 in Northern California starts out winding between Santa Clara and Santa Cruz counties for several miles, due to mountainous geography...

[Bryant5493]

Georgia State Route 141 begins at U.S. 19/S.R. 9 in Buckhead (in Fulton County), goes into DeKalb County, then Gwinnett County, then re-enters Fulton County (Johns Creek) and then terminates its "life" at Georgia 400, south of Cumming.


Be well,

Bryant

[hbelkins]

If I am not mistaken, the Blue Ridge Parkway meanders across county lines several times through Virginia.

There are several instances of this in Kentucky, probably too numerous to mention. For those of you who like Kentucky's four-digit routes, KY 2022 does this. Begins at Buckhorn in Perry County, crosses a very remote corner of Owsley County, then terminates in a "landlocked" area of Perry County where you cannot reach this area by highway without going out of the county. I believe Froggie drove this paved goat path when he made a trip to eastern Kentucky a few years ago.

[xonhulu]

US 212 approaching Yellowstone goes from MT into WY, then back into MT, where it technically ends at the park boundary.  However, if you continue you enter WY again inside the park.

Doesn't I-86/NY 17 briefly enter PA?

[corco]

To elaborate on US-212, it appears that the US Forest Service maintains the road within Wyoming, as that's the only place you'll find reassurance shields without identifying markers in Wyoming, and the signs are really old, but built to Wyoming spec (2di width). The only normal WYDOT signs you'll find are the ones right by the WYO 296 junction for that highway.



Also, if you want to be technical, US-212 again enters Wyoming from Montana and clips the northeastern corner of the state before heading into South Dakota


Also in Wyoming, US-191 briefly re-enters Wyoming from Montana and then leaves it again just north of W. Yellowstone, Mont.


Wyoming State Highway 70 actually enters Colorado, but Wyoming keeps maintenance...

Wyoming informs you you're leaving Wyoming, but doesn't tell you what state you're entering


Then in the 2/3 of a mile or so WYO 70 is in Colorado there's one significant WYDOT sign for the post office in Slater, Colo.


Then you re-enter Wyoming

[Ian]

Well, there is an interesting case of Maine route 113. It briefly enters New Hampshire, twice! And it is even signed as ME 113 in NH! What is more bizarre is that there is even a spur off of ME 113 in NH, that is NH 113B. Odd occurance of a Maine route's spur being a NH route.t

There is also MD/DE 54 that straddles along the DE/MD border on the southern part of DE.

[WNYroadgeek]

PA 426 enters New York, becomes NY 426, re-enters Pennsylvania, and becomes PA 426 again.

[xonhulu]

To elaborate on US-212, it appears that the US Forest Service maintains the road within Wyoming, as that's the only place you'll find reassurance shields without identifying markers in Wyoming, and the signs are really old, but built to Wyoming spec (2di width). The only normal WYDOT signs you'll find are the ones right by the WYO 296 junction for that highway.

Is it the Forest Service or Park Service?  I passed what looked like a highway maintenance facility climbing up to Beartooth Pass that had a Park Service shield at the gate and thought that was pretty odd.

Also, if you want to be technical, US-212 again enters Wyoming from Montana and clips the northeastern corner of the state before heading into South Dakota

Forgot about this one, but you're right.

Also in Wyoming, US-191 briefly re-enters Wyoming from Montana and then leaves it again just north of W. Yellowstone, Mont.

I also forgot about this one, which I drove last summer on the way home.  It also re-enters Yellowstone National Park (entrance signs and all); this stretch is noteworthy because I saw 2 US 191 shields posted here proving that some US Routes are signed in Yellowstone!

[Ian]

There is also NJ 440 that enters New York, becomes NY 440, then enters back into New Jersey becoming NJ 440 again.

[PAHighways]

Doesn't I-86/NY 17 briefly enter PA?

Yes, but it is maintained by NYSDOT and NYSP has jurisdiction.

[Chris]

US 212 approaching Yellowstone goes from MT into WY, then back into MT, where it technically ends at the park boundary.  However, if you continue you enter WY again inside the park.

And again in far northeastern Wyoming.

US 50 runs through extreme southwest Maryland, then enters WV and VA, and then enters MD again at Washington.

I think we had this topic before though.