This map section of Colorado shows the location of the main sites visited and photographed along the Union Pacific Railroad (UP) line between Dotsero and the west portal of the Moffat Tunnel.

This second map shows the route of the Denver & Salt Lake Railway (D&SL), previously known as the Denver Northwestern & Pacific Railway (DN&P) prior to bankruptcy and reorganization in 1913, between Denver and Craig, Colorado.

Prior to the construction of the Moffat Tunnel the Denver Northwestern & Pacific Railway crossed the Rocky Mountains Front Range over Rollins Pass at an elevation of 11,690 feet until the Rollins Pass route was abandoned in 193O.