The building housing the Tumble Inn was moved to Powder River from Ten Sleep, Wyoming, in 1923.

The Yellowstone Highway crossed the North Platte River on a bridge recently demolished. The former Standard Oil refinery grounds beyond, west of Casper, have been converted to open space and athletic fields. 

Yellowstone Highway in Wyoming and Colorado, 1916

The Yellowstone Highway and old U.S. Highway 20-26 crossed the South Fork of the Powder River west of Casper.

The Atlantic Yellowstone Pacific Hiway Association was established  after the Yellowstone Highway. “AYP” was often painted over the black “H” on Yellowstone Highway trail markers.