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
Indiana State Road 51 Indiana State Road 51 State Road 51 in the U.S. state of Indiana is a north–south route on the state highway system in northwest Indiana. It consists of a route long from a point on U.S. Route 30 (Lincoln Highway) east of Merrillville and west of Valparaiso, north to U.S. Route 20 in Gary. Immediately north of US 30, the highway is signed as the Adam Benjamin Highway. SR 51 travels north on Lake Park Avenue from US 30, crossing Old Lincoln Highway and the mainline of the Canadian National Railway in the former town of Ainsworth before turning east