None in Indiana, but these are nearby:
Putnam County, IL - the infamous I-180
Adams County, IL - I-172
Allegan and Van Buren Counties, MI - I-196 [forgot 94 goes through Van Buren]
I'm sure there's a few in Kansas that I-135 goes through.
Douglas, WI
Santa Clara county, CA
San Mateo County, CA are counties that have at least two or more 3di but no 2di.
These freeways are I-280, I-380, I-680 and I-880
Niagara County, NY - I-190
Livingston County, NY - I-390 (although it should be a 2di...)
Richmond County, NY - I-278
Kings County, NY - I-278, I-478
Queens County, NY - I-278, I-678, I-295, I-695
Nassau County, NY - I-495
Suffolk County, NY - I-495
Monmouth County, NJ - I-195
Ocean County, NJ - I-195
Lycoming County, PA - I-180 (but it does have future I-99...)
Windham County, CT - a very near-miss with I-395, but I-84 clips the corner.
Linn County IA where Cedar Rapids is. Only served by I-380.
It looks like Ohio only have one instance, with I-275 in Clermont County.
Across the river, Campbell County, KY have I-275 and I-471, and no 2di.
I'm sure I missed one here and there, but here's what I came up with.
Marin, CA (I-580)
San Mateo, CA (I-280, I-380)
Santa Clara, CA (I-280, I-680, I-880)
Franklin, WA (I-182)
Carson City, NV (I-580)
McPherson, KS (I-135)
Harvey, KS (I-135)
Dakota, NE (I-129)
Douglas, WI (I-535)
Black Hawk, IA (I-380)
Buchanan, IA (I-380)
Benton, IA (I-380)
Linn, IA (I-380)
Adams, IL (I-172)
Putnam, IL (I-180)
Monroe, IL (I-255)
Allegan, MI (I-196)
Poinsett, AR (I-555)
Craighead, AR (I-555)
Jefferson, AR (I-530)
Madison, AL (I-565)
Dyer, TN (I-155)
Campbell, KY (I-275, I-471)
Butler, KY (I-165)
Ohio, KY (I-165)
Daviess, KY (I-165)
Hall, GA (I-985)
Pickens, GA (I-575)
Muscogee, GA (I-185)
Pinellas, FL (I-175, I-275, I-375)
Brunswick, NC (I-140)
Wayne, NC (I-795)
City of Suffolk, VA (I-664)
City of Hopewell, VA (I-295)
City of Roanoke, VA (I-581)
City of Portsmouth, VA (I-264)
Montgomery, MD (I-270, I-370, I-495)
Lycoming, PA (I-180)
Clermont, OH (I-275)
Monmouth, NJ (I-195)
Ocean, NH (I-195)
Niagara, NY (I-190)
Livingston, NY (I-390)
Richmond, NY (I-278)
Kings, NY (I-278, I-478)
Queens, NY (I-278, I-495, I-678, I-878)
Nassau, NY (I-495)
Suffolk, NY (I-495)
Plymouth, MA (I-195, I-495)
Sagadahoc, ME (I-295)
Chris
Allegan Co, MI
Montgomery County, MD (which also happens to be the state's most populous county): I-270, I-370, & I-495.
I-95 misses MoCo by about a mile where it leaves the beltway at exit 27 in PG County, and I-70 misses MoCo by less than a mile at exit 68 in Mt. Airy (the quad-point of Frederick, Montgomery, Howard & Carroll counties is just to the south of I-70 here).
Quote from: jmacswimmer on September 20, 2021, 01:03:38 PM
Montgomery County, MD (which also happens to be the state's most populous county): I-270, I-370, & I-495.
I-95 misses MoCo by about a mile where it leaves the beltway at exit 27 in PG County, and I-70 misses MoCo by less than a mile at exit 68 in Mt. Airy (the quad-point of Frederick, Montgomery, Howard & Carroll counties is just to the south of I-70 here).
I was just looking in the DC area to see if I missed any and was typing that as you posted. Good find.
Chris
Quote from: jayhawkco on September 20, 2021, 01:05:48 PM
Quote from: jmacswimmer on September 20, 2021, 01:03:38 PM
Montgomery County, MD (which also happens to be the state's most populous county): I-270, I-370, & I-495.
..
I was just looking in the DC area to see if I missed any and was typing that as you posted. Good find.
You can also add Kings County, NY (Brooklyn), noted above in my reply #5.
Quote from: webny99 on September 20, 2021, 01:19:24 PM
Quote from: jayhawkco on September 20, 2021, 01:05:48 PM
Quote from: jmacswimmer on September 20, 2021, 01:03:38 PM
Montgomery County, MD (which also happens to be the state's most populous county): I-270, I-370, & I-495.
..
I was just looking in the DC area to see if I missed any and was typing that as you posted. Good find.
You can also add Kings County, NY (Brooklyn), noted above in my reply #5.
I meant to do that. I somehow mentally merged Brooklyn and Staten Island when I was typing.
Chris
I believe I-575 just barely enters Pickens County, GA.
Franklin County, WA - I-182
No winners along Hidden I-595 east of DC? That because of I-97?
Quote from: jmacswimmer on September 20, 2021, 01:03:38 PM
Montgomery County, MD (which also happens to be the state's most populous county): I-270, I-370, & I-495.
I-95 misses MoCo by about a mile where it leaves the beltway at exit 27 in PG County, and I-70 misses MoCo by less than a mile at exit 68 in Mt. Airy (the quad-point of Frederick, Montgomery, Howard & Carroll counties is just to the south of I-70 here).
Man, you stole mine!
Rockingham County, NC will eventually have I-785.
Quote from: ilpt4u on September 20, 2021, 09:27:10 PM
No winners along Hidden I-595 east of DC? That because of I-97?
Both Prince George's and Anne Arundel counties have 2DIs (95 and 97).
Quote from: dvferyance on September 20, 2021, 12:36:15 PM
Linn County IA where Cedar Rapids is. Only served by I-380.
I-380 also goes through Benton, Buchanan and Black Hawk Counties.
Nebraska has I-129 enter Dakota County.
The city of Portsmouth, VA only has I-264.
In the very near future, Greene and Pitt Counties in North Carolina will only have I-587. The highway has been fully approved by the FHWA and AASHTO to be designated along the US-264 freeway, it's only a matter of time until NCDOT begins to officially sign the roadway.
Quote from: sprjus4 on September 21, 2021, 06:29:27 AM
In the very near future, Greene and Pitt Counties in North Carolina will only have I-587. The highway has been fully approved by the FHWA and AASHTO to be designated along the US-264 freeway, it's only a matter of time until NCDOT begins to officially sign the roadway.
And for now, Wayne County, North Carolina only has I-795. I-42 is coming soon.
Kentucky is fixing to get a bunch as various parkways are converted to 3di routes.
St Charles Parish, LA-- Interstate 310
That may be all I can think of...
Arkansas has five counties at present. I-540 serves Sebastian County (Fort Smith) but that will change once I-49 is built out. Two counties are served only by I-530 (Jefferson and a corner of Grant). I-555 serves Poinsett and Craighead Counties.
Surprised to see no one has mentioned I-476 in Pennsylvania. There must be at least one along that road.
Quote from: KCRoadFan on September 21, 2021, 11:17:09 PM
Surprised to see no one has mentioned I-476 in Pennsylvania. There must be at least one along that road.
Actually not. In the counties I-476 goes through:
Delaware: I-95
Montgomery: I-76
Bucks: I-95
Lehigh: I-78
Carbon: I-80
Luzerne: I-80
Lackawanna: I-84
Salem County, NJ only has I-295.