AARoads Forum

Non-Road Boards => Off-Topic => Travel Mapping => Topic started by: oscar on December 14, 2015, 10:51:36 PM

Title: Highways in Grand Canyon National Park
Post by: oscar on December 14, 2015, 10:51:36 PM
This is an Arizona-specific followup to one of my posts in the U.S. National Park Highways topic.

The AASHTO U.S. routes database, http://route.transportation.org/Pages/U.S.RouteNumberDatabase(Dec2009).aspx shows that US 180's west end is at the south entrance to Grand Canyon NP, rather than continuing into the park as TM and CHM have it. This is similar to the situation with U.S. routes in the Yellowstone NP area, though not necessarily other national parks (for example, AASHTO has parts of US 34 and US 36 within Rocky Mountain NP in Colorado).

It also looks like, per Arizona DOT, there's a lengthy gap in AZ 64 between the south and east entrances to Grand Canyon NP, rather than the route continuing through the South Rim part of the park as TM and CHM have it:

http://www.azdot.gov/docs/default-source/planning/2013shslog.pdf?sfvrsn=2 (scroll down to p. 183).

A few pages later, the log for AZ 67 indicates that state-maintained route ends at the Grand Canyon NP North Rim entrance, but AZ 67 signage continues within the park.

I haven't taken a close look in GMSV on AZ 64 or AZ 67 within the park. Some BBSes in the South Rim area include AZ 64 markers, to point visitors to the park exits where they can continue on AZ 64.

I'll leave the rest for others to follow up. From what I've seen, I'm a little more convinced that US 180 should be truncated out of Grand Canyon NP, than that AZ 64 needs to be split, with that and AZ 67 truncated to park entrances.

If we re-map AZ 64 to remove it from the park, South Entrance Rd. and East Rim Dr. would be prime candidates for addition to the in-dev U.S. National Parks Highways (usanp) route set, to ultimately fill the gap in AZ 64.
Title: Re: Highways in Grand Canyon National Park
Post by: Mapmikey on December 15, 2015, 06:27:30 AM
There are numerous AZ-64 shields (some are green!) on brown signs within the park (with no US 180 shields) without TO banners and AZ-64's mile markers are signed continuously through the park.

The US 180-AZ 64 overlay is signed with AZ-64's mile markers as well.

Mike
Title: Re: Highways in Grand Canyon National Park
Post by: english si on December 15, 2015, 09:24:43 AM
So it would be truncate US180 and leave everything else alone?
Title: Re: Highways in Grand Canyon National Park
Post by: oscar on December 15, 2015, 08:40:06 PM
So it would be truncate US180 and leave everything else alone?

Yeah, probably. I'm a big believer in going with what states and their DOTs say on whether specific state routes enter/cross or not national parks. But if Arizona DOT is sending mixed signals on AZ 64 and AZ 67, our default should be to leave them alone until we get better information. The milemarkers within GCNP, that Mapmikey mentioned, seem to muddy the waters since they sound like Arizona DOT's doing rather than National Park Service signage.

Assuming that US 180's route file gets truncated, AZ 64's would need to be tweaked to add at least a hidden point at GCNP's south entrance, to preserve the concurrency between the park entrance and the AZ 64/US 180 split south of the park.