This 1938 photo shows the construction for Highway 40 overpass that crosses the Union Pacific Railroad line, just north of downtown Colfax. In 1963 the State renamed this section Route 174, which took traffic away from the downtown run the Lincoln Highway had made and allowed traffic to skirt the downtown area and proceed more quickly to Grass Valley and beyond.

The above map shows the Lincoln Highway route, in purple, and the site of the Highway 40 bridge. The Quonset huts were a motel made from a series of surplus Quonset huts leftover from WWII. Here is a link to an article about the motel.