Near Fort Laramie, Wyoming is the old military bridge constructed in 1875-76 over the North Platte River. The trussed iron bridge consistes three bowed spans each 140 feet in length. It is believed to be the oldest existing military bridge west of the Mississippi River. The old Cheyenne to Deadwood Route once crossed this bridge as numerous prospectors fled to the Black Hills in search of gold. Amazingly, the bridge remained in use until 1958. Photo by Kathy Weiser-Alexander.