Shortest Single-Digit State Highway

[Road Hog]

Think I found a candidate: AR 4 in Polk County, AR. Runs three miles from US 71 to the Oklahoma state line.

(As is AHTD custom, AR 4 resumes clear on the other side of the state in a 22-mile loop in Desha County. The part in the middle was redesignated US 278. So that's 25 total miles, but there can't be many that are shorter.)

[Kacie Jane]

All three of NJ's single digit routes are well shorter than 25, and NJ 5 is just over three miles.

(The shortest in Washington is SR 8 at 20 miles, the rest of the single-digit routes are over 50.)

[CentralCAroadgeek]

California's shortest single-digit would have to be the 6.7 mile CA-7 in the Imperial Valley. All it does is connect I-8 with the Mexican border.

[bulldog1979]

M-8 in Michigan: 5.491 miles through Detroit and Highland Park would be the shortest for Michigan, unless we could count only the Michigan segment of US 8 at 2.322 miles.

[NE2]

http://en.wikipedia.org/wiki/West_Virginia_Route_6
Half a mile at most.

[Mark68]

Colorado State Highway 1, from US 285 in northern Fort Collins to I-25 in Wellington.

Approximately 10 miles.

State Highway 3 in Durango (mostly 8th Ave).

2 and a half miles.

State Highway 8 (Morrison Rd) from Wadsworth Blvd (SH 121) in Lakewood southeast to Morrison, then south to US 285.

8.68 miles.

[Brandon]

Illinois 6 for a grand total of 10.11 miles.  It's also mostly freeway with the exception being the ramp to Illinois 29.  That may make it the shortest mostly freeway single-digit state route.
http://en.wikipedia.org/wiki/Illinois_6

[mjb2002]

South Carolina Route 2, which is only in the Cities of Cayce and West Columbia.

[Takumi]

NC's single digit routes are often pretty short. I think the only noteworthy one is 8. NC 2 is 5 miles long, 5 is 8 miles, all 4 versions of NC 6 were 8 miles or less, NC 7 is 12 miles, and old NC 3 (now NC 136) was 2 miles. None of Virginia's single digit state routes are under 10 miles; the shortest are VA 4 (11 miles) and VA 9 (13 miles) which both go to state borders.

[roadman65]

NJ 5 is only 3 miles in Bergen County, NJ. 

[deathtopumpkins]

Pretty much every single-digit state highway in New England is fairly long. The only exception I can think of is NH 4, which is a 3.9 mile extension of ME 4 in Dover.
Annoyingly, it's only a few miles away from US 4.

[Alps]

All three of NJ's single digit routes are well shorter than 25, and NJ 5 is just over three miles.

(The shortest in Washington is SR 8 at 20 miles, the rest of the single-digit routes are over 50.)

All three? Which one are you creatively excluding?

NY: 2
CT: 3
RI: 4
MA: 4
VT: 3
PA: 3
DE: 3
MD: 8

That exhausts my area of knowledge.

[Eth]

All of the ones in Georgia are pretty long; the shortest is SR 6, at 72 miles.  This probably has a lot to do with the fact that most of Georgia's single-digit-SR mileage follows US highways.

[WillWeaverRVA]

VA 4 is the shortest at about 11 miles. VA 9 is the second shortest at 13 miles, but continues as WV 9 at the West Virginia state line.

[roadman65]

All three of NJ's single digit routes are well shorter than 25, and NJ 5 is just over three miles.

(The shortest in Washington is SR 8 at 20 miles, the rest of the single-digit routes are over 50.)

I did not see this post as I scrolled through this thread.  Anyway if I saw it my post would have been then Ditto to Kacie Jane on NJ 5 being just over 3 miles.

I did though realize that the eastern segment of FL 2 is only 15 miles long.  Although all of FL 2 (both segments) are close to 70 miles in total length.

In PA you have PA 5 that is short to add to Steve's post that he could not think of.

[sandiaman]

   In  the  Land  of  Enchantment:
  It  would  have  to  be  NM  7, at  the  entrance  to  Carlsbad  Caverns  National Park.  Less  than  a  mile  long.  On  the  other  hand,  NM  9  is  the  longest  state  highway,approximately  80  miles  in length.  It  runs  along  the  Mexican  border,  a  favorite  route   for  coyotes  and  drug  runners.

[NE2]

On  the  other  hand,  NM  9  is  the  longest  state  highway,approximately  80  miles  in length.  It  runs  along  the  Mexican  border,  a  favorite  route   for  coyotes  and  drug  runners.

And spacebars?

[Kacie Jane]

All three of NJ's single digit routes are well shorter than 25, and NJ 5 is just over three miles.

(The shortest in Washington is SR 8 at 20 miles, the rest of the single-digit routes are over 50.)

All three? Which one are you creatively excluding?

Somehow I forgot NJ 4.    But it's 0.01 miles shorter than NJ 3, the longest of the three I remembered, so the remainder of my statement holds.

[sandiaman]

I'm  so  sorry.

[Kacie Jane]

May I smack him with a fish?  Please?

[hbelkins]

I think Kentucky's champion would be KY 5, which I drove the entirety of yesterday. And the route is definitely signed, counter to a statement that well-known buffoon Carl Rogers made a few years ago.

http://en.wikipedia.org/wiki/West_Virginia_Route_6
Half a mile at most.

And, as the Wiki article states, not posted. It's signed as To US 60 and To WV 61.

[english si]

Even if you ignore the little places (Jersey, Isle of Man, Luxembourg, etc) and the incomplete networks/motorways numbered due to being part of route x that continues the route onwards, then you still have some very short 1-digit motorways in Europe:

Northern Ireland (OK, it's a province with its own numbering system) has the M3 at 1.2 miles, and the M5 at 1.5 miles
The A5 in the Netherlands was recently extended from 4.6 miles to 8.8 miles (and will nearly reach 10 miles when finished)
The A3 in France (the country which is the largest in size in the EU) is only 8.9 miles.

The best one overall (that I know of) is the A8 on the Isle of Man - unsigned, half a mile, most of which seems to have been downgraded (physically) recently, giving you this 260 yard route that google gives as a 3 minute walk. I found it when looking on the Government's GIS service. It wasn't the original A8, so it seems like they declared this road an A road and took the lowest free number. Jersey's A7 is 1.5 miles and signed.

[mjb2002]

SAM RITTENBURG BLVD in Charleston would qualify as well. That is the name for South Carolina Route 7, the only other single digit route in the state that is less than ten miles.

[DandyDan]

MO 1 is 7.2 miles in the KC area.  The southern K-8 is 1.3 miles and goes south from Kiowa into Oklahoma.

[apeman33]

MO 1 is 7.2 miles in the KC area.  The southern K-8 is 1.3 miles and goes south from Kiowa into Oklahoma.

Like AR 4, each used to be much longer. IIRC, U.S. 281 took over most of what was K-8.