Longest continuous stretch of decomissioned US highway...

[thenetwork]

This might make for a good puzzler:

What is the longest stretch of a decommissioned US Highway in the country?

Restrictions:

• The highway must be continuous and accessible by vehicle (This eliminates many "chunks" of Route 66)
• The highway must not be listed as any other numbered US, State or Interstate highway, and cannot be signed as a Historic Highway (Again, keeping out the Route 66 factor).

Have fun.

[corco]

The best I can think of in Wyoming is the stretch of US-85 from Lusk to Newcastle at 50 miles

There are some decent long stretches of old 99 in Washington, but all are broken up by random state routes that travel with it for a block or two and none are over 50 miles to my knowledge.

[agentsteel53]

US-16 between Mitchell and Oacoma, SD is 72 miles (including the serviceable preservation of the old bridge at Chamberlain!), but it is broken up with a brief multiplex with state route 45 at Kimball, rendering the segment split at 50 + 22 miles.

there may be longer segments on US-10 in North Dakota or Montana, and maybe even Idaho.  The route exists quite admirably in both states; it's just those brief sectional-line multiplexes that may kill the calculation.

speaking of Idaho, US-30 may be a candidate, and North Dakota, we could try US-81. 
Post Merge: December 31, 1969, 06:59:59 PM
I believe you can follow US-10 from Cataldo, ID to Saltese, MT, which is 52 miles.  However, while a continuous road does exist, it is part Old US 10, part Silver Creek Road, and part Old Yellowstone Trail, so I do not know if that was ever a single continuous alignment of US-10.  Also, there are a few places where I-90 overlaps it and the road has been realigned to pass underneath the freeway.
Post Merge: December 11, 2010, 10:15:10 AM
10 can be followed from Montana 47 on a completely unique alignment, undisturbed by the freeway, all the way east to past Forsyth - 62 miles!  At that point there are several freeway undercrossings and the road continues another 12 miles before tapering out. 

[Hot Rod Hootenanny]

(Old) Lincoln Highway-Old US 30 from near the Ohio-Indiana border to Mansfield (where it becomes Oh 430).

[agentsteel53]

in Kansas, US-40 heading west from Russell.  Choosing the double-bypassed CITY US 40 alignment through Hays, (which, amazingly, still has a surviving sign for it!) and avoiding the multiplex with BYPASS US 183, we can head 63.0 miles west before reaching a brief multiplex with US-283 in Wakeeney.

At that point, one can travel another 32.3 miles west to a multiplex with Kansas 23, and then another 22.4 miles west to where US-40 crosses under I-70 at Oakley and becomes a separate active state-maintained route. 

So, a total of 119.7 miles with only two brief, incidental multiplexes, and 63.0 without them.  Not bad.

[mightyace]

(Old) Lincoln Highway-Old US 30 from near the Ohio-Indiana border to Mansfield (where it becomes Oh 430).

I pretty sure it's interrupted some places by state routes on the old alignment, primarily in towns.

Van Wert, OH - possibly OH 118
Delphos, OH - OH 66 and OH 99
Beaverdam, OH - OH 696 east to I-75 and current US 30
Upper Sandusky, OH - OH 53 and 199
Bucyrus, OH - OH 19 and 100
Crestline, OH - OH 181

[Tarkus]

there may be longer segments on US-10 in North Dakota or Montana, and maybe even Idaho.  The route exists quite admirably in both states; it's just those brief sectional-line multiplexes that may kill the calculation.

There's a couple decent stretches in Washington, even.  Between WA-10, University Way in Ellensburg and the Kittitas County-maintained Vantage Highway east of Ellensburg, you're probably looking at a good 60 miles.  There's probably been a bit of change west of town to facilitate the flow of the I-90/US-97 interchange, however, but otherwise, it's largely in tact.  I don't know if much of WA-970 or WA-903 through Cle Elum were ever part of US-10, but if they were, it'd be closer to 70 miles.

-Alex (Tarkus)

[agentsteel53]

it's 30 miles to the I-90 bridge across the Columbia River from Ellensburg. 

then there's another bridge just west of Moses Lake that is served by I-90, but if you leave Moses Lake, you get over 80 miles of old road (a section of which is the incredibly named Max Harder Rd.), some of which has been redone to facilitate I-90 crossings, and some of which is multiplexed with WA-21. 


Post Merge: December 31, 1969, 06:59:59 PM
is Idaho 81 an active state route?  Google Maps cosigns it as ID-81 and County Route 30S.  You can follow it from the old 30N/30S split in Burley all the way to the Utah state line, 59.0 miles.  And if Utah 42 isn't on the books anymore, you can follow old US-30S to Utah 30, which is another 7.8 miles. 

all of that route is former US-30S.
Post Merge: December 11, 2010, 10:16:10 AM
speaking of Utah: US-40 may be followed for about 40.6 miles from Knolls to Wendover.  A couple more, if UT-58 is off the books.  At that point, you cross into Nevada, where Google Maps shows old US-40 as NV-58 (an incorrect designation for sure).  Then, you can follow US-40 in Nevada for at least a few more miles, but it looks like I-80 was built on top of the old road, as the frontage road simply peters out.  I do not know how 40 ran between West Wendover and Wells.

A lot of Nevada's business loops are state highways, but there may be a stretch of US-40 in the state that is quite long. 

[corco]

is Idaho 81 an active state route?

It is, but it only goes to Malta at the junction with Idaho 77. South of there, it's CR 30S despite what most maps would have you believe

[usends]

Google shows a distance of 184 miles along old US 16 between Austin MN and Brandon SD (outside Sioux Falls).  As far as I can tell, this segment has only a few multiplexes, each of them brief ones through towns.  For purists, it looks like the longest stretch along that segment without a single multiplex would be from Brandon to Jackson MN, which is about 81 miles.

[Alps]

There's quite a good bit of old US 61 in Minnesota that's just County Route 61.  You never said County Routes didn't count.

[Quillz]

Wouldn't it be US-99 if it wasn't for the historic route markers? I believe the original 1926 routing still exists, albeit today it's a series of various state highways, Interstates and poorly maintained roads.

[froggie]

For purists, it looks like the longest stretch along that segment without a single multiplex would be from Brandon to Jackson MN, which is about 81 miles.

Except for the duplex with US 59 (and partially MN 60 too) in Worthington.

There's quite a good bit of old US 61 in Minnesota that's just County Route 61.  You never said County Routes didn't count.

There is.  But the longest part of that which doesn't involve a state route is only about 25 miles.

[thenetwork]

There's quite a good bit of old US 61 in Minnesota that's just County Route 61.  You never said County Routes didn't count.

That is true because if it was a decommissioned US hwy and not renumbered as another state or US Highway, it is probably a county or city-maintained highway with some sort of city/county route number attached -- noted on a sign or not.

I'm also willing to say that it is OK if the old US highway briefly multiplexes with an existing signed non-interstate highway due to some of the previous factors mentioned above (through a smaller town, on a bridge over a major railroad or waterway, etc...)  I think any multiplex(es) under 10 miles per stretch is a fair requirement.

[roadfro]

speaking of Utah: US-40 may be followed for about 40.6 miles from Knolls to Wendover.  A couple more, if UT-58 is off the books.  At that point, you cross into Nevada, where Google Maps shows old US-40 as NV-58 (an incorrect designation for sure).  Then, you can follow US-40 in Nevada for at least a few more miles, but it looks like I-80 was built on top of the old road, as the frontage road simply peters out.  I do not know how 40 ran between West Wendover and Wells.

A lot of Nevada's business loops are state highways, but there may be a stretch of US-40 in the state that is quite long. 

UT-58 is still on the books as far as I'm aware, so old US 40 doesn't quite make it in to Wendover. If UT-58 were to be decommissioned, one could get a little ways into West Wendover in Nevada but then it would be broken up as old US 40 (I-80 Bus) overlaps for a couple blocks with US 93 Alt. US 40 was mostly covered up by I-80.

Practically all of Nevada's I-80 business loops are state highways, with most of these loops primarily following the old US 40. There's a number of frontage roads and state highways that were formerly US 40, but very few (if any) go much more than 10 or so miles.

[usends]

For purists, it looks like the longest stretch along that segment without a single multiplex would be from Brandon to Jackson MN, which is about 81 miles.

Except for the duplex with US 59 (and partially MN 60 too) in Worthington.

I don't think the original US 16 used any part of modern US 59 or MN 60.  I suspect traffic was routed right through downtown, and then exited to the east via East Av.

[dfilpus]

For purists, it looks like the longest stretch along that segment without a single multiplex would be from Brandon to Jackson MN, which is about 81 miles.

Except for the duplex with US 59 (and partially MN 60 too) in Worthington.

I don't think the original US 16 used any part of modern US 59 or MN 60.  I suspect traffic was routed right through downtown, and then exited to the east via East Av.

According to http://deadpioneer.com/projects/routes/US16/US16map.html "Deadpioneer's Historic Minnesota Highways", the pre-1942 routing was along East Ave, Sherwood, 12th St, 2nd Ave, 10th St, 10th Ave, Diagonal Road, which does not share any routing with US 59.

[froggie]

I don't think the original US 16 used any part of modern US 59 or MN 60.  I suspect traffic was routed right through downtown, and then exited to the east via East Av.

Original US 16 didn't use modern US 59 or MN 60, but as best as I can tell, original US 16 did multiplex with original US 59 and possibly MN 60.  The whole lot was moved out of downtown in 1942.

But therein lies another question with the OP's first query...do you go with the routing as it existed when decommissioned?  Or the original routing?  Or some combination thereof?

I ask this because if we go with the original routing, then there was a 1 block duplex of US 16 and US 75 in Luverne at the beginning of the U.S. highway system.