Maryland will be difficult - Virginia has these same sorts of routes but put them in their own separate system (F-routes). A lot of unsigned Maryland state highways fail criteria #4 though. I would be happy to assist in deciding which ones should be included. BTW, MD 856 is completely drivable on its original narrow-width concrete...
Are there Virginia state routes, serving universities/colleges, etc., where we've mapped only the best-signed part of the primary state route mileage? If so, we may need to add more roads to be mappable unsigned routes.
I recall there was a similar issue for spur routes on Utah public university campuses, though I'm not sure we left anything out (since Tim supervised the drafting of usaut, that probably didn't happen).
Only the Virginia Facility Routes that have a full state highway shield posted somewhere are in TM.
Separately, there are a number of these routes that are signed in the field only with the white rectangles that have not previously been welcomed in TM and are thus far not there.
These are: 209, 300Y, 313, 333, 335, 342, 345, 355, 375, 388, 389
These are the completely unposted ones I could add the publicly drivable portions (11 of these have been posted at some point since the mid 90s, just not right now): 113, 192, 213, 246, 261, 283, 317, 324, 325, 329, 332, 337 Alt (norfolk), 350, 366, 368, 377, 381, 384, 390, 393, 394, 404, 405, 420
These are the completely unposted ones I would not add:
48 (ROW for Blue Ridge Pkwy and Skyline Dr)
302 (too many segments and no "main segment")
303 (too many segments although Letcher Ave could be considered the main segment)
315 (not sure this is an actual road anymore)
318 (state capitol drive - not publicly accessible; newly expanded part has too many segments so unless one of these is signed...)
327 (too many segments and no main segment)
328 (don't think this is a road anymore)
339 (configuration has changed...would need to field check if this can be driven without going through gates)
367 (not sure this is still in the system - the comm college is not there anymore and this was a multi-segment route though a main segment does still exist)
382 (would need 3 segments)
I am on the fence about 399 because that could be construed as a parking lot