This also opens up a question about whether non-motorized routes should be in or not, given that MI 185 is. This also affects West River Parkway in NY (which was removed from TM but the situation is still ambiguous especially given the criteria for inclusion in usanyp). Is MI 185 the only example of a road closed to cars but still in TM, similar to how the interstates are the only roads that are allowed to be in without signage? Or are there actual criteria determining whether a road officially and permanently closed to cars gets to remain?
M-185 is the only road I know of in TM that prohibits all motorized traffic, though there are a couple other examples that prohibit
cars:
- the summit of Prospect Mountain Highway in NY, which is closed to cars but can be clinched via shuttle bus (and possibly sometimes by motorcycle?)
- Truck US 219 in Ridgway, PA, which normally prohibits cars and is supposed to be used by trucks only but... this is not enforced (I've clinched it in a car, no one stopped me)
Normally a road which is permanently or indefinitely closed to motorized traffic is not included. See for example:
- the northern end of CA 39 (legally closed to all users, though unenforced if you are inclined to hike it)
- the middle section of CA 173 (legally closed to motorized traffic except if needed for evacuation purposes, otherwise explicitly open to non-motorized traffic)
- the eastern end of AK 10 in Cordova (isolated from all other roads by a washout which will likely never be repaired)
- Crater Rim Drive in Hawaii Volcanoes National Park (most of the road is closed to all users due to volcano hazards, part of it has physically collapsed)