Idaho State Highway 51 February 2015, some map products such as Google Maps still show SH-51's former overlay with American Legion Blvd. SH-51's northern terminus is in the city of Mountain Home in Elmore County. After turning south from Airbase Rd. and the intersection with SH-67, the road crosses the Snake River into Owyhee County and passes through the towns of Bruneau, Grasmere, and Riddle. About from the state border it enters the Duck Valley Indian Reservation. As the road crosses into Nevada it becomes State Route 225. The reservation's only major town, Owyhee is about south of the state border. After another through
Minnesota State Highway 51 Highway 51 parallels State Highway 280 through Falcon Heights and the Midway neighborhood of Saint Paul. State Highway 51 was authorized in 1933. The route was paved by 1935. The original alignment on the south end of Highway 51 was from West 7th Street up Edgecumbe Road to Snelling Avenue. This section of Highway 51 was later rerouted to Montreal Avenue. From 1934 to 1935, the north end of Highway 51 previously followed Snelling Avenue northbound to County Road B in Roseville, then 51 turned westbound to Fairview Avenue and ran northbound along Fairview Avenue and New Brighton Road to