The bridges are based on Union Pacific Railroad Prototype bridges in Weber Canyon, Utah. The closest bridges to what Bob modified them to resemble are located at Croiden ,Utah for many years one was painted silver, the other green, then one was partially repainted for awhile. The bridges in the canyon have never been very clean looking. The Riverside section on my layout is modeled after the Devils Gate Tunnel area where photos show twin tunnels, and twin bridges,there is no third track or tunnel where my branch line is and of course no railrioad station . Nate Goodman (Nato).