Idaho State Highway 51 Idaho State Highway 51 State Highway 51 (SH-51) is a state highway in southwestern Idaho from Mountain Home south to the Nevada border, where it continues as State Route 225 to Elko. It is the major north–south road in Owyhee County. As currently configured in the state's official milepoint log, SH-51 terminates at the BL-84 intersection with American Legion Blvd., and is not otherwise officially concurrent/overlaid with BL-84 (where the signs at I-84's Exits 90 and 99 say "To SH-51/To SH-67") or the former section of US-20 that follows American Legion Blvd. to I-84/US-20 east at Exit 95. As of
New York State Route 51 north from West Winfield to Utica. At the time, this was the only substantial segment of what is now NY 51 to have a route number even though all of modern NY 51 south of Ilion was state-maintained. In the 1930 renumbering of state highways in New York, most of NY 44 became part of NY 8. The section from West Burlington to West Winfield, however, became part of the new NY 51, which utilized all of its modern routing from Mount Upton to Ilion upon assignment. It was extended across the Mohawk River to NY 5 in North Ilion