How many Hidden Route Highways or Freeways have you been on?

[agentsteel53]

I've been on a good deal of unsigned routes in Nevada, since several state routes in urban areas are notorious for not being well signed. SR 171 (the McCarran Airport connector to I-215) is the only freeway-grade state highway in Nevada, and also isn't signed.

I don't really think 171 needs to be signed.  at airports (where lots of out-of-towners congregate), I think a system of fewer signs is the way to go.  to add 171 to the mix of 215, 515, etc is just asking to overwhelm motorists.

[Doctor Whom]

Maryland:  I-495X, I-595, and presumably lots of letter-suffixed inventory routes

California:  I-305

Florida:  SR 400

New Jersey:  444, 446, and 700

Virginia:  402, 420, and various routes in Arlington County and incorporated areas to which the state assigns inventory numbers.  It's probably cheating to mention 90004 and 90005, although I've been on both of those.

DC:  I-695 before it was signed

[Ned Weasel]

Oh geez, somehow I spaced out and forgot all about NJ 444 and 700!  I've driven those, too (though only part of NJ 444), as have many people on here.  To be honest, the only hidden route designations I usually pay attention to are the ones that I don't think should be hidden, which are usually portions of US routes that are conveniently left unsigned.

Edit: I also forgot NJ 446--the one measly time I've driven it!  Although I do remember the date: 7/7/2007 (there was a riveting discussion on the radio at the time, about how some people thought it was lucky and other people thought it was just another day).

[Roadsguy]

Is 700 the secret number for the NJTP south of 276 the PA Spur?

Anyway, here's some of mine, all of which are in PA:

• PA 283 ("secretly" SR 300)
• The (Harrisburg Int'l) Airport Connector (SR 3032)
• The Central Scranton Expressway (SR 3022)
• PA 3 (actually a lot of unsigned 4-digit routes for all of its length in Philly proper)
• All the unsigned roads that PennDOT maintains.

[Ned Weasel]

Is 700 the secret number for the NJTP south of 276 the PA Spur?

Yes.

[Charles2]

All U.S. routes in Alabama have unsigned state route companions:

U.S. 11-AL 7
U.S. 29-AL 15
U.S. 31-AL 3
U.S. 43-AL 13/17/171 (each of which is a signed independent route along parts of their ways)
U.S. 45-AL 17/57
U.S. 72-AL 2
U.S. 78-AL 4 (although AL 4 has been co-signed with U.S. 78 along Corridor X [I-22])
U.S. 80-AL 8
U.S. 82-AL 6
U.S. 84-AL 12
U.S. 90-AL 16
U.S. 98-AL 42
U.S. 231-AL 1/53 (AL 53 is a signed independent route from Huntsville to Ardmore)
U.S. 278-AL 118/AL 74 (Although there a few AL 118 signs posted with 278 from the Mississippi state line to Guin, and AL 118 is routed along the former U.S.78 from Guin to Jasper; also, SR-74 is signed along the former U.S. 78 from the Mississippi state line to Hamilton)
U.S. 280-AL 38
U.S. 331-AL 9 (AL 9 is a standalone route from Wetumpka to the Georgia state line)
U.S. 411-AL 25 (AL 25 is a standalone route from Wilcox County in the SW part of the state to Leeds, but north of Leeds it is unsigned)
U.S. 431-AL 1

---And I've been on all of these routes. 

Also, all 2-digit interstates in Alabama are internally coded as AL-6xx (610, 620, 659, 665, and 685).  I'm not sure if there are internal codes for the 3-digit routes in the state (165, 359, 459, 565 and 759), or what the future codings are for I-22, the proposed I-422 or the eventually-designated I-685.

[seanpatf]

In Texas
Interstate 345 Downtown Dallas

In Tennessee
Interstate 124 Chattanooga

In Louisiana
Interstate 910 New Orleans (Gretna)

In Montana
Interstate 315 Great Falls

In Oklahoma
Interstate 444 Tulsa