Getting from Illinois to the rest of the country

[hotdogPi]

Simple question: Can you reach at least half of counties in the US from a numbered route in Illinois? (You can reach 45 states – all except AK, HI, VT, NH, and ME. 276 of 435 congressional districts. Surprisingly, the three largest non-Chicago cities, New York, Los Angeles, and Houston, are all excluded.)

It would be interesting to see a map of the US showing all counties you can reach from Illinois.

[Max Rockatansky]

If California didn't decide to try to kill off the US Route system in the 1960s that number would be just a little bit higher. 

[paulthemapguy]

Counties are way smaller than states. Not to rain on anyone's parade, but this sounds like it should be an easy "no."  Have you seen how far laterally the clinched area spreads from a route on people's county maps?  It isn't much. Here's mine, as an example.

[hotdogPi]

Counties are way smaller than states. Not to rain on anyone's parade, but this sounds like it should be an easy "no."  Have you seen how far laterally the clinched area spreads from a route on people's county maps?  It isn't much. Here's mine, as an example.

I'm also guessing that the answer is "no", but:
* Your map has four lines crossing ND/SD/NE/KS/OK. Potential routes to those states include I-94, I-90, I-80, I-70, US 12, US 20, US 24, US 30, US 34, US 36, US 40, US 50, US 60, and that doesn't even include diagonals like US 62. There's also a decent number in Virginia that connect.
* California's county sizes are large, so the penalty for very few routes reaching California is reduced.

[Konza]

OK, let's think this through.

US routes in Illinois:  6, 12, 14, 20, 24, 30, 34, 36, 40, 41, 45, 50, 51, 52, 54, 60, 62, 67, 136, 150

Former US routes in Illinois:  66, 460

Main line Interstate routes in Illinois:  24, 39, 41, 55, 57, 64, 70, 72, 74, 80, 88, 90, 94

Just between US 6, US 41, and I-90 this stretches from Miami to Seattle and southern California to Cape Cod.  US 67 takes it to the Big Bend in Texas, and US 52 to the Canadian border in North Dakota and the Atlantic Coast in South Carolina. 

If these routes don't reach half the counties, they almost surely reach counties that border half of them.

[hotdogPi]

OK, let's think this through.

US routes in Illinois:  6, 12, 14, 20, 24, 30, 34, 36, 40, 41, 45, 50, 51, 52, 54, 60, 62, 67, 136, 150

Former US routes in Illinois:  66, 460

Main line Interstate routes in Illinois:  24, 39, 41, 55, 57, 64, 70, 72, 74, 80, 88, 90, 94

Just between US 6, US 41, and I-90 this stretches from Miami to Seattle and southern California to Cape Cod.  US 67 takes it to the Big Bend in Texas, and US 52 to the Canadian border in North Dakota and the Atlantic Coast in South Carolina. 

If these routes don't reach half the counties, they almost surely reach counties that border half of them.

IL/WI 35 and WY/NE/IA/IL 92 will add a few more. Not sure about other state routes.

[webny99]

Interesting concept! If we're going to get a proper answer and not just a guesstimate, it really needs to be taken state-by-state.
So starting with New York: Assuming I-88 doesn't count, we've got four routes that enter both Illinois and New York: I-90, US 6, US 20, and (bonus!) US 62, representing NY's 62 counties.

I-90 (16) Chautauqua, Erie, Genesee, Monroe, Ontario, Seneca, Cayuga, Onondaga, Madison, Oneida, Herkimer, Montgomery, Schenectady, Albany, Rensslaer, Columbia
US 6 (4) Orange, Rockland*, Westchester, Putnam
US 20 (3) Many of the same counties as I-90, plus Livingston, Otsego, and Schoharie
US 62 (2) Cattaraugus, Niagara

Erie and Chautauqua Counties have I-90, US 20, and US 62, making them the only NY counties to get 3 routes to Illinois.
25 counties out of 62 total makes 40.3%. That's actually fewer than I thought, but not bad considering how sparse US routes are around here.


*Questionable, but I'm counting it.


Even without getting an exact answer for Pennsylvania (which I do plan to do shortly), it's safe to assume it will be well over 50%.
They've got I-70, I-80, US 6, US 30, US 40, US 62, I-90/US 20 in Erie County, and probably some more that I'm missing. And unlike I-90/US-20 in New York, each route takes its own course and you're not going to get double-ups all the way across the state.

[Konza]

Arizona:

US 60 enters 6 counties:  Apache, Navajo, Gila, Pinal, Maricopa, La Paz.

New Mexico:

US 54 enters 5 counties:  Quay, Guadelupe, Lincoln, Torrence, and Otero.
US 60 enters 5 counties that US 54 doesn't:  Catron, Socorro, De Baca, Roosevelt, and Curry
US 62 enters 2 counties:  Eddy and Lea.

If US 66 were still active, you would add 3 counties in Arizona (Mohave, Yavapai, and Coconino) and 4 in New Mexico (Bernalillo, Cibola, McKinley, and Santa Fe).

[Some one]

Texas
Current
US 54 (4): El Paso; Hartley, Dallam, Sherman
US 60 (10): Parmer, Castro, Deaf Smith, Randall, Potter, Carson, Gray, Roberts, Hemphill, Lipscomb
US 62 (12)  El Paso, Hudspeth, Culberson; Gaines, Terry, Hockley, Lubbock, Crosby, Floyd, Motley, Cottle, Childress
US 67 (26!): Presidio, Brewster, Pecos, Crockett, Crane, Upton, Reagan, Irion, Tom Green, Runnels, Coleman, Brown, Comanche, Erath, Somervell, Johnson, Ellis, Dallas, Rockwall, Hunt, Hopkins, Franklin, Titus, Morris, Cass, Bowie

Former
US 66 (8): Deaf Smith, Oldham, Potter, Carson, Gray, Donley, Wheeler

[bassoon1986]

Illinois highways only give a tiny bit of Louisiana.


I-55 and US 51- the same 3 parishes: Tangipahoa, Livingston, St. John the Baptist. (Just a sliver of Livingston. Isn't marked)


iPhone

[pianocello]

In Florida, the only route that goes to Illinois is US 41. That's 15 counties out of 67.

I'll tackle Iowa. It's nicely broken down into neatly organized rows of counties. Things get weird on the eastern end, so I'm putting Clinton, Scott, and Muscatine counties in the 6th tier in case anyone is following along:

• In the northernmost 3 tiers, the only Illinois route that passes through is US 52. It goes through 3 of those counties. Also formerly, US 20 went through two of the counties before the freeway was built west of Waterloo.
• US 20 runs through all 12 counties in the 4th tier.
• The 5th tier has US 30 for the 9 of the 12 counties (Crawford to Linn). Of the other three, IA(/IL) 64 goes through two of them. 11 counties in total.
• In the 6th tier: US 30 goes through Harrison, the next three no longer have any common routes since IA 64 was truncated, and the last 8 have I-80. Adding in Muscatine (US 6) and Clinton (US 30), that's 11.
• 7th tier all has IA 92. 10 counties.
• 8th tier all has US 34. 11 counties.
• 9th/southern tier all has IA 2, which becomes IL 9 at the river. If that's allowed, that's 10 counties. If not, I think it's only one (US 136 in Lee county).

In total, I count 68 of 99 (or 59, depending on whether IA 2/IL 9 counts). Historically, it was at least as many as 73 (or 64).

[oscar]

California:

US 6: Inyo and Mono Counties

US 50: Yolo, Sacramento, and El Dorado Counties

Nevada (which like California also has large counties):

US 6:  Esmeralda, Nye, and White Pine Counties

US 50: Carson City independent city, and Douglas, Lyon, Churchill, and Lander Counties (plus White Pine County, covered by US 6)

So 13 non-duplicative counties between CA and NV.

Oregon and Washington have counties along I-90, US 12, US 20, and US 30, if someone else wants to do counts for those states.

[hotdogPi]

California:

US 6: Inyo and Mono Counties

US 50: Yolo, Sacramento, and El Dorado Counties

Nevada (which like California also has large counties):

US 6:  Esmeralda, Nye, and White Pine Counties

US 50: Carson City independent city, and Douglas, Lyon, Churchill, and Lander Counties (plus White Pine County, covered by US 6)

So 13 non-duplicative counties between CA and NV.

I-80?

[oscar]

I-80?

Overlooked that.

I-80 adds San Francisco, Alameda, Contra Costa, Solano, Placer, Nevada, and Sierra Counties in California, and Washoe, Storey (just barely), Pershing, Humboldt, and Elko Counties in Nevada, upping the CA/NV total to 25.

[Scott5114]

Oklahoma "shouldn't" share any routes with Illinois since it's on a diagonal with it, but Cairo is really far south, and US-62 is wacky, so it shares US-54 (panhandle only), US-60, and US-62.

US-54: Texas County (1)
US-60: Ellis, Dewey, Major, Garfield, Grant, Kay, Osage, Washington, Nowata, CraIG, Delaware, Ottawa (12)
US-62: Harmon, Jackson, Kiowa, Comanche, Caddo, Grady, McClain, Cleveland, Oklahoma, Lincoln, Okfuskee, Okmulgee, Muskogee, Cherokee, Adair (15)

So that's 28 counties between those three highways. You can reach 36% of the counties in Oklahoma just by following routes that also pass through Illinois.

Then there's the matter of US-66. I don't think you should count it because it's not an active highway any longer, and most of the corridor is now served by I-40 and I-44, neither of which enter Illinois. However, if you insist: Beckham, Washita, Custer, Caddo, Canadian, Oklahoma, Lincoln, Creek, Tulsa, Wagoner, Rogers, CraIG, Delaware, Ottawa. 14 counties, or 7 new ones when you remove duplicates from US-60 and US-62.  That would give you a total of 35 counties in Oklahoma including US-66.

[TheHighwayMan3561]

Minnesota (excluding repeats)
I-94: Washington, Ramsey, Hennepin, Wright, Stearns, Todd, Douglas, Grant, Otter Tail, Wilkin, Clay

I-90: Winona, Olmsted, Mower, Freeborn, Martin, Jackson, Nobles, Rock

US 12: Meeker, Kandiyohi, Swift, Big Stone

US 14: Dodge, Steele, Waseca, Blue Earth, Brown, Redwood, Lyon, Lincoln

US 52: Fillmore, Goodhue, Dakota

[ftballfan]

Michigan (25/83)
Via I-94: Berrien, Van Buren, Kalamazoo, Calhoun, Jackson, Washtenaw, Wayne, Macomb, St. Clair (9)
Via US-12 (and not on I-94): Cass, St. Joseph, Branch, Hillsdale, Lenawee (5)
Via US-24 (and not on I-94): Monroe, Oakland (2)
Via US-41: Menominee, Delta, Alger, Marquette, Baraga, Houghton, Keweenaw (7)
Via US-45: Gogebic, Ontonagon (2)

Wisconsin (42/72)
Via I-39: Rock, Dane, Columbia, Marquette, Waushara, Portage, Marathon (7)
Via I-90 (and not on I-39): Sauk, Juneau, Monroe, La Crosse (4)
Via I-94 (and not on I-39 or I-90): Kenosha, Racine, Milwaukee, Waukesha, Jefferson, Jackson, Trempealeau, Eau Claire, Dunn, St. Croix (10)
Via US-12 (and not on any above route): Walworth, Clark, Chippewa (3)
Via US-14 (and not on any above route): Iowa, Richland, Vernon (3)
Via US-41 (and not on any above route): Washington, Dodge, Fond du Lac, Winnebago, Outagamie, Brown, Oconto, Marinette (8)
Via US-45 (and not on any above route): Waupaca, Shawano, Langlade, Oneida, Vilas (5)
Via US-51 (and not on any above route): Lincoln, Iron (2)
There used to be even more counties that qualified when US-61 and US-151 briefly entered Illinois in the Dubuque area (Grant, Lafayette, Crawford, Calumet, Manitowoc)

Indiana (66/92)
Via I-64: Posey, Vanderburgh, Gibson, Warrick, Spencer, Dubois, Perry, Crawford, Harrison, Floyd (10)
Via I-70: Vigo, Clay, Putnam, Morgan, Hendricks, Marion, Hancock, Henry, Wayne (9)
Via I-74 (and not on any above route): Vermillion, Fountain, Montgomery, Boone, Shelby, Rush (barely), Decatur, Franklin, Ripley, Dearborn (10)
Via I-80/I-90: Lake, Porter, LaPorte, St. Joseph, Elkhart, LaGrange, Steuben (7)
[I-94, US-12, US-20, US-40, and US-136 bring no new counties to the table]
Via US-6 (and not on any above route): Marshall, Noble, DeKalb (3)
Via US-24: Newton, Jasper, White, Cass, Miami, Wabash, Huntington, Whitley, Allen (9)
Via US-30 (and not on any above route): Starke, Kosciusko (2)
Via US-36 (and not on any above route): Parke, Madison, Randolph (3)
Via US-41 (and not on any above route): Benton, Warren, Sullivan, Knox (4)
Via US-50 (and not on any above route): Daviess, Martin, Lawrence, Jackson, Jennings (5)
Via US-52 (and not on any above route): Tippecanoe, Clinton (2)
Via US-150 (and not on any above route): Orange, Washington (2)

[webny99]

Even without getting an exact answer for Pennsylvania (which I do plan to do shortly), it's safe to assume it will be well over 50%.

I'm quite enjoying this. Got some good tunes going for round #2... here goes

Pennsylvania
I-80 (15): Mercer, Venango, Bulter, Clarion, Jefferson, Clearfield, Centre, Clinton, Union, Northumberland, Montour, Columbia, Luzerne, Carbon, Monroe
I-70 (5): Washington, Westmoreland, Somerset, Bedford, Fulton
I-90 / US 20 (1): Erie
US 6 (10): Crawford, Warren, McKean, Potter, Tioga, Bradford, Wyoming, Lackawanna, Wayne, Pike
US 30 (10): Beaver, Allegheny, Franklin, Adams, York, Lancaster, Chester, Delaware, Montgomery, Philadelphia
US 40 (1): Fayette
US 62 (1): Forest
Total 43 of 67 (64.2%)

(Cross check of 24 remaining counties: Elk, Cameron, Lycoming, Sullivan, Susquehanna, Northampton, Bucks, Lehigh, Berks, Schuylkill, Lebanon, Dauphin, Cumberland, Perry, Snyder, Juniata, Mifflin, Huntingdon, Blair, Cambria, Indiana, Armstrong, Lawrence, Greene.)

New Jersey
I-80 (6): Warren, Sussex, Morris, Essex, Passaic, Bergen
US 30 (2): Camden, Atlantic
US 40 (2): Gloucester, Salem
Total 10 of 21 (47.6%)

Delaware
US 40 (1): New Castle
Total 1 of 3 (33.3%)

Maryland
I-70 (5): Washington, Frederick, Carroll, Howard, Baltimore
US 40 (5): Garrett, Allegany, Baltimore City, Harford, Cecil
US 50 (7): Prince George's, Anne Arundel, Queen Anne's, Talbot, Dorchester, Wicomico, Worcester
Total 17 of 24 (70.8%)

(Cross check of 7 remaining counties: Montgomery, Kent, Caroline, Somerset, St. Mary's, Calvert, Charles.)

[Konza]

Duplicates omitted; the county is listed with the first route on the list.

Missouri (73 of 115; 78 with US 66):

Via US 136 (9):  Atchison, Nodaway, Gentry, Harrison, Mercer, Putnam, Schuyler, Scotland, Clark.
Via US 36 (also IL 110) (8):   Buchanan, DeKalb, Caldwell, Livingston, Linn, Macon, Shelby, Marion.
Via US 24 (7):  Ralls, Monroe, Randolph, Chariton, Carroll, Lafayette, Jackson.
Via US 40/I-70 (8):  St. Louis City, St. Louis County, Warren, Montgomery, Callaway, Boone, Cooper, Saline, Lafayette.
Via US 54 (9):  Pike, Andrain, Cole, Miller, Camden, Hickory, St. Clair, Cedar, Vernon.
Via US 50 (7):  Franklin, Gasconade, Osage, Montreal, Morgan, Pettis, Johnson
Via US 67 (5):  Jefferson, St. Francois, Madison, Wayne, Butler.
Via I-55 (6):  Ste. Genevieve, Perry, Cape Girardeau, Scott, New Madrid, Pemiscot
Via US 60 (13):  Mississippi, Stoddard, Butler, Carter, Shannon, Howell, Texas, Wright, Webster, Greene, Christian, Barry, Newton.
Via US 62 (1):  Dunklin.

US 66 adds 5 counties:  Crawford, Phelps, Pulaski, Laclede, Jasper.

[Konza]

Again, the county is listed with the first route listed.

Kansas (70 of 105, 71 with US 66):

Via US 36 (13):  Cheyenne, Rawlins, Decatur, Norton, Phillips, Smith, Jewewll, Republic, Washington, Marshall, Nemaha, Brown, Doniphan.
Via US 24 (15):  Sherman, Thomas, Sheridan, Graham, Rooks, Osborne, Mitchell, Cloud, Clay, Riley, Pottawattomie, Shawnee, Jefferson, Leavenworth, Wyandotte.
Via US 40/I-70 (12):  Wallace, Logan, Gove, Trego, Ellis, Russell, Ellsworth, Saline, Dickinson, Geary, Waubaunsee, Douglas.
Via US 54 (13):  Bourbon, Allen, Woodson, Greenwood, Butler, Sedgwick, Kingman, Pratt, Kiowa, Ford, Clark, Meade, Seward.
Via US 50 (17):  Johnson, Miami, Franklin, Osage, Coffey, Lyon, Chase, Marion, Harvey, Reno, Stafford, Edwards, Ford, Gray, Finney, Kearney, Hamilton.

US 66 adds Cherokee County, in the far southeast corner of the state.

[webny99]

Pro tip for those who use mob-rule.com: Overlay your travels on Google Maps for this exercise. You can see routes, county lines, and county names, so no need to juggle multiple tabs! 


Another question that came to mind: Is it worth doing this exercise for other central states, or is it guaranteed out of the gate that Illinois has the most county connections of any state?  Obviously, having all of US 20, US 30, US 40, US 50, US 60, I-70, I-80 and I-90 is a big advantage that no other states have. Indiana and Ohio come close, but both miss out on US 60, while the interstates fan out as you head west.

[Konza]

Illinois is connected to the southwest by US 54, US 60, US 62, and US 67, but Indiana has connections to the east and southeast via US 27, US 31, US 33, US 35, US 231, and US 421.  There are more counties in a lot of the eastern states than in the western states, and most of the states north of the 37th parallel to the west would be the same for both, the differences being US 14 and US 54.

There's a reason they call themselves "The Crossroads of America"...

[Scott5114]

Pro tip for those who use mob-rule.com: Overlay your travels on Google Maps for this exercise. You can see routes, county lines, and county names, so no need to juggle multiple tabs! 

In many cases, you can also just go to "U.S. Route xx in yy" (like "U.S. Route 60 in Oklahoma") on Wikipedia, and there will be a list of counties there on the junction list. If a route passes through a county but doesn't have any junctions there, it will still be listed, with "No junctions".

Another question that came to mind: Is it worth doing this exercise for other central states, or is it guaranteed out of the gate that Illinois has the most county connections of any state?

Stretching the definition of "central state", but Texas has such a disgusting number of routes passing through it that it would probably give Illinois a run for its money, especially since US-62 and US-67 are among them.

[US 89]

Okay, I’ll do Utah. Leaving out duplicates:

I-70 and US 50: Millard, Sevier, Emery, Grand
I-80: Tooele, Salt Lake, Summit
US 6: Juab, Utah, Wasatch, Carbon
US 40: Duchesne, Uintah
Historic US 30S: Box Elder, Weber, Davis, Morgan, Summit

So that’s 13 of Utah’s 29 counties covered by extant routes. But US 30 was split into a 30N and 30S before I-84 became a thing, so if you add in the additional counties on old 30S you’re up to 17/29.

[hotdogPi]

Wisconsin (42/72)
Via I-39: Rock, Dane, Columbia, Marquette, Waushara, Portage, Marathon (7)
Via I-90 (and not on I-39): Sauk, Juneau, Monroe, La Crosse (4)
Via I-94 (and not on I-39 or I-90): Kenosha, Racine, Milwaukee, Waukesha, Jefferson, Jackson, Trempealeau, Eau Claire, Dunn, St. Croix (10)
Via US-12 (and not on any above route): Walworth, Clark, Chippewa (3)
Via US-14 (and not on any above route): Iowa, Richland, Vernon (3)
Via US-41 (and not on any above route): Washington, Dodge, Fond du Lac, Winnebago, Outagamie, Brown, Oconto, Marinette (8)
Via US-45 (and not on any above route): Waupaca, Shawano, Langlade, Oneida, Vilas (5)
Via US-51 (and not on any above route): Lincoln, Iron (2)
There used to be even more counties that qualified when US-61 and US-151 briefly entered Illinois in the Dubuque area (Grant, Lafayette, Crawford, Calumet, Manitowoc)

IL/WI 35?