Doing some research last week, I came across a couple of topo maps that show CA 120's third segment - between 395 & 6 - as incomplete. Specifically, it's the section that crosses Adobe Creek. The topo maps show it as just a trail as late as 1957 while the much smaller scale Caltrans maps show it as a completed roadway well before that time.
The bridge log does not list it because there isn't really a bridge.
Any insight?
It's certainly a completed route as of today, albeit one that often sees winter closure.
According to the 1963 Caltrans map, that particular segment was still only "oiled earth" between the eastern terminus at Benton Station and about 44 miles to the west, but west of there, to about Mono Lake, it was paved.
A 1954 aerial shows the modern alignment at Adobe Creek.
Here are some 1939 photos of the road, which could certainly be called a trail: http://archive.org/stream/california193940highwacalirich#page/6/mode/2up
Quote from: NE2 on January 23, 2017, 01:49:37 AM
A 1954 aerial shows the modern alignment at Adobe Creek.
Here are some 1939 photos of the road, which could certainly be called a trail: http://archive.org/stream/california193940highwacalirich#page/6/mode/2up
Certainly looks like a trail to me, given the area that it is in I suppose that really isn't surprising. I'd have to look back but I know other highways like 25 (previously discussed in two threads) certainly was still fording creeks by the mid-20th century. There wouldn't be much of a reason for upgrades given things like Mono Mills and Benton Hot Springs were essentially already dead localities even by then.
Quote from: NE2 on January 23, 2017, 01:49:37 AM
A 1954 aerial shows the modern alignment at Adobe Creek.
Here are some 1939 photos of the road, which could certainly be called a trail: http://archive.org/stream/california193940highwacalirich#page/6/mode/2up
Thanks for linking that. The sections in the mountains are shown on the map to be in pretty rough shape as well but this gives an idea of how rough it actually was up there. It's a little crazy that they would slap a state highway designation on that. That's barely a forest road.
There's a larger collection of Mono County hi-res aerials at Berkeley, and I'm going to be up there this week, so I may try to get in there. It seems like they have a lot of highway history in their collections.