Largest US Counties In Each State Without a US Highway or an Interstate

[CoreySamson]

I recently saw we just had a thread about the largest (in population) cities without an Interstate connection or a US Highway connection.
So I thought, what if we applied the same idea to counties? What is the largest county without a US Highway or an Interstate?

I'll start off by naming my county, Brazoria County, Texas. It only has state highways, but it has a population of approx 370k (in 2018 per Wikipedia)

I'm curious to see which county is the largest in each state!

[NWI_Irish96]

In Indiana, Monroe County is the largest without a US highway at 137,974.
Howard County is the largest without an interstate at 82,752.
Fayette County is the largest without either at 24,277.

[ilpt4u]

In Indiana, Monroe County is the largest without a US highway at 137,974.

Monroe County/Bloomington is an odd one. It was recently on the list of no Interstate nor US Highway, while at the same time is on the western route of the Old Dixie Highway

So it has an old N-S "national" highway, but that never graduated to a US Route nor Interstate. Dixie Highway is basically Old IN 37 thru this area. I guess between Bloomington and Indy Old Dixie Highway is finally graduating to Interstate status, as "New" IN 37 is being upgraded to I-69

[US 89]

The largest county in Utah without an interstate is Cache County (pop. 127,068). Washington County (pop. 171,100) is currently the largest in the state without a US highway, but it was historically served by US 91. There is only one county in Utah has never had any kind of US highway (or interstate, for that matter), and that is Wayne County with its 2,690 people.

[Max Rockatansky]

Probably Tulare County in California at about 442,000 residents. 

[Hwy 61 Revisited]

PA:
- Cambria County is the most populous without an Interstate.
- Cameron County is the most populous without a US Highway (and also the least populous county in the state). However, PA 120 used to be a US Highway, so this probably doesn't count.

[Rothman]

This isn't already a thread?  Odd.

[dfilpus]

North Carolina only has one county without an Interstate or a US Highway: Pamlico, population 13144.

[dvferyance]

In Wisconsin it's Wood County population 74,000.

[interstate73]

In New York that would be my current home base of Tompkins County, population 102,000. Although someone at the City of Ithaca thinks otherwise  https://www.google.com/maps/@42.4407435,-76.5106004,3a,40.7y,152.81h,91.6t/data=!3m6!1e1!3m4!1sje27aJbNbk_DP4EfTCC0IA!2e0!7i16384!8i8192

[TheHighwayMan3561]

In Minnesota you have to drop all the way to Roseau County (13,500; 54th of 87). We're very well served by US and interstates.

[GaryV]

In Michigan it would be Barry County, population 60k.

Lenawee County with 98k would be the largest without an Interstate, but it has 3 US highways.

[bassoon1986]

Louisiana only has 5 parishes without an interstate or a US highway. Washington Parish, the toe of the boot, is the largest at 46,690. That's more people than I would have thought.


iPhone

[Verlanka]

North Carolina only has one county without an Interstate or a US Highway: Pamlico, population 13144.

With the insane amount of interstates in North Carolina, I'm not surprised.

[Eth]

Georgia's largest county with neither is Fayette County (pop. 107,500), 22nd out of 159 in population.

[dfilpus]

North Carolina only has one county without an Interstate or a US Highway: Pamlico, population 13144.

With the insane amount of interstates in North Carolina, I'm not surprised.

It's really the uniform spread of US highways across the state. The Interstates actually go through a minority of counties, but the US highways go everywhere.

[Beltway]

Oahu -- Population: 953,207 (2010)

[CNGL-Leudimin]

Kings County, NY (a.k.a. Brooklyn). 2.5 million people, no US Routes and never has had one . San Diego County, CA has even a larger population at 3.3 million and also no US Routes, but it had US 80, 101 and 395 in the past. However both of them have Interstates (and so does Honolulu -not Oahu- county in Hawaii), so Tulare may be currently the winner. It, however, had US 99 in the past, so I wonder what is the largest county which has never been served by a nationally-numbered route.

[sprjus4]

Oahu -- Population: 953,207 (2010)

I-H1, I-H2, I-H3, I-H201.

[oscar]

Oahu -- Population: 953,207 (2010)

I-H1, I-H2, I-H3, I-H201.

The state's second-most populous county, Hawaii County (the "Big Island") works, with no Interstate or US routes, and a population of about 185,000.

The OP specified population, but Hawaii County is also largest in Hawaii for land area (about 4028 square miles, depending on what Madame Pele has been up to lately). That would be among the larger counties in land area, though it's well behind Alaska's North Slope Borough (over 88,000 square miles, larger than most U.S. states), which also has no Interstate or US routes.

[webny99]

Upstate New York is tailor-made for this thread!
My home county of Monroe (NY) has about 750,000 residents and zero (0) US Routes! We do, of course, have interstates, and many state routes.
Neighboring Wayne County fits the OP's criteria: no Interstates OR US routes, and a population of 90,064.

Other NY counties that qualify are:
Tompkins, pop. 102,793
Schuyler, pop. 17,912
Yates, pop. 24,841
Orleans, pop. 40,612
Fulton, pop. 53,591
Hamilton, pop. 4,434
Lewis, pop. 26,447

And... nothing downstate qualifies, so I guess that's it!
There are 8 qualifying counties out of 62 total counties.
Population-wise, Tompkins is 16th of 62, and the only county with a population over 100K to qualify.
Wayne County is 18th of 62, while Hamilton County is dead last, 62nd of 62.

All population figures are 2018 US Census estimates.

[froggie]

Only one of these in Vermont...Lamoille.  None in New Hampshire.

[CoreySamson]

So here's what we've got so far:

California: Tulare County pop. 442,000
Texas: Brazoria County pop. 370,200
Hawaii: Hawaii County pop. 185,000
Georgia: Fayette County pop. 107,500
New York: Tompkins County pop. 102,793
Rhode Island: Newport County pop. 82,888
Wisconsin: Wood County pop. 74,000
Michigan: Barry County pop. 60,000
Louisiana: Washington Parish pop. 46,690
Virginia: Independent City of Manassas pop. 41,641
Iowa: Marion County pop. 33,309
Illinois: Randolph County pop. 32,546
Missouri: Polk County pop. 31,137
Alabama: Geneva County pop. 26,421
Arkansas: Cleburne County pop. 25,230
Indiana: Fayette County pop. 24,277
South Dakota: Clay County pop. 13,864
Minnesota: Roseau County pop. 13,500
North Carolina: Pamlico County pop. 13,144
Utah: Wayne County pop. 2,690

States with no counties either serviced by a US Route or an Interstate:
New Hampshire, Nevada, Delaware, Connecticut

I'll keep adding to this list once we get more states.

Edit: This list is no longer being kept up to date. See my list on page 2 of this thread for accurate information.

[formulanone]

Alabama has 3 counties without a US Route or Interstate Highway:

Geneva: pop. 26,421
Clay: pop. 13,932
Wilcox: pop. 11,670

...so Geneva County would be Alabama's most-populous county in this category, ranked 40th out of 67 by population in the state. 

[hobsini2]

In Illinois,
Counties without either:
Stark
Menard
Crawford
Wabash
Edwards
Randolph
Hardin
Pope

The answer is Randolph at 32,546.