Longest route within one specific county in your own state

[roadman65]

I was wondering which route, whether Interstate, US, or state has the longest county run within the state you live in.

In mine, Florida, it would be US 1 in Monroe County as it is well over 110 miles spanning all the Keys between Key West and the Florida Peninsula.  Even I-95 in Brevard County, which is over 70 miles in transiting is not as long intracounty as US 1 is further south.

What route number in your state has the longest county run?

[dfilpus]

North Carolina: NC 12, 90 miles in Dare County. No other route or county comes close.

[vtk]

In Ohio, it's probably I-270.  Its 54.97 miles are all in Franklin County.  Close behind is OH 7 in Washington County, at 54.03 miles.

[vdeane]

NY 30 spends 83.8 miles in Hamilton County.  I can't think of anywhere higher off the top of my head.

[bzakharin]

Garden State Parkway or US 9 in Ocean county is ~ 42 miles. Probably can't top that in NJ.

[SSOWorld]

WIS 13 in Bayfield County is my best estimate for WI, though some E/W route in Marathon county might beat it.

[Pete from Boston]

In Mass. it would be hard to beat the ~70 miles of US 6 in Barnstable County.

[gonealookin]

Nevada's champion is US 93 in Lincoln County, at 172.401 miles.

US 93 also is the runner-up, with 141.824 miles in Elko County.

The interstate highway winner is I-80 in Elko County (132.726 miles) and the state highway winner is Nevada 140 in Humboldt County (110.113 miles).

[jwolfer]

I was wondering which route, whether Interstate, US, or state has the longest county run within the state you live in.

In mine, Florida, it would be US 1 in Monroe County as it is well over 110 miles spanning all the Keys between Key West and the Florida Peninsula.  Even I-95 in Brevard County, which is over 70 miles in transiting is not as long intracounty as US 1 is further south.

What route number in your state has the longest county run?

US1 in Monroe is longest for sure. I would guess us1 in brevard is 2nd

[route17fan]

NY 30 spends 83.8 miles in Hamilton County.  I can't think of anywhere higher off the top of my head.

Hey Val - is NY 27 longer? I'm thinking on the north side of 90 miles

[route17fan]

Oops - I forgot to specify - NY 27 in Suffolk County.

[SD Mapman]

SD 44 in Pennington County has 89 miles andSD 34 in Meade County has 83 miles.

[Mapmikey]

In Virginia I believe the winners are:

US 13 in Northampton Co - 50 miles
US 17 in Fauquier - 49
US 58 in Lee - 48

Mapmikey

[vdeane]

NY 30 spends 83.8 miles in Hamilton County.  I can't think of anywhere higher off the top of my head.

Hey Val - is NY 27 longer? I'm thinking on the north side of 90 miles

I KNEW I saw a reference marker that high in CAMCI (NYSDOT's really awesome map-based internal viewer of everything - and before you ask, no, it's not viewable outside our intranet)!  Couldn't remember where though and thought I transposed a couple of numbers.

Based on that, here's to top roadways/county for NY:
1. NY 27, Suffolk: 92.6
2. NY 30, Hamilton: 83.8
3. NY 30, Franklin: 78.4*
4. NY 25, Suffolk: 75.0
5. NY 22, Washington: 73.6

*79.6 if the small section south of the 0.5 mile dip into St. Lawrence County is added in; in total the distance on NY 30 from the Hamilton County line to Canada is 80.1 miles

[bassoon1986]

Top 5 for Louisiana

LA 82 - Cameron Parish - 83.8 miles
LA 1 - Lafourche Parish - 81.3 miles
LA 23 - Plaquemines Parish - 68.7 miles
LA 1 in Caddo Parish - northbound is 67.5 miles
LA 27 Cameron parish - 64.6 miles

I had guessed a good chunk of these. Some of the next highest ones were surprising though.

[wxfree]

I'm pretty sure in Texas it's I-10 across Pecos County, at just over 100 miles.  An interesting sub-category is the longest highway entirely in one county, which for Texas I think is TX 54 in Culberson County, at 55 miles.

[kendancy66]

All of I-40 in CA, is in San Bernadino County.  Google Maps says that Needles to Barstow is 144 miles.  County route 66 continues on to Victorville.  I estimated its length at 200 miles

[pianocello]

In Iowa, it's probably I-80 in Pottawattamie County, with just under 49 miles. I also checked US 169 in Kossuth County, it has about 48 miles.

[tdindy88]

For Indiana, it may be I-465 for most of its length with the exception of between Exits 25 and 37, so about 40 miles in Marion County alone. US 41 in Lake County is next at about 38 miles. I think those would be the longest there.

[GaryV]

In MI, I'd guess either US-2 in Gogebic County or M-22 in Leelenau County.  Both in the neighborhood of 70 miles.

Honorable mentions go to US-2 in Mackinac County and I-75 in Oakland County.

[JustDrive]

I-15 travels a total of 188 miles in San Bernardino County.  I think it's the most mileage of any state route in any county in California.

[hbelkins]

Kentucky's champion would have to be KY 194 in Pike County. 72.819 miles from the Floyd County line to the Virginia state line, and that doesn't count a short concurrency with KY 1426 (former US 119).

[bulldog1979]

In MI, I'd guess either US-2 in Gogebic County or M-22 in Leelenau County.  Both in the neighborhood of 70 miles.

Honorable mentions go to US-2 in Mackinac County and I-75 in Oakland County.

M-22 in Leelanau County: 66.97 miles
US 2 in Gogebic County: 64.33 miles
US 2 in Mackinac County: 62.25 miles
US 41 in Marquette County: 60.87 miles
M-28 in Marquette County: 52.98 miles
I-75 in Oakland County: 47.30 miles

[jp the roadgeek]

For CT, it's US 7 in Litchfield County at 41 miles.  For RI, US 1 in South County (36 mi)

[Brandon]

I-90, I-94, and I-294 all spend 52 miles in Cook County, Illinois.