State Route 257 is a highway in central Utah that runs from the junction of SR-21 in Milford to US-6/US-50 sixty-nine miles (111 kilometers) to the north in Hinckley. There are no junctions with any other state highways along SR-257.
Route description 
From its southern terminus in Beaver County, SR-257 generally north until Black Rock, where it makes a turn to the northwest. It stays north-northwest until the northern terminus of the route, located in Millard County. Most of the route is paralleled by the Union Pacific Railroad.
The northernmost piece of SR-257 became a state highway in 1933 as part of State Route 140, a short connection from SR-27 (now US-6) near Hinckley south to Deseret and east via Oasis to SR-26 (now US-50) at Harding. The remainder was not created until 1955, when the state legislature added the road between SR-21 in Milford and SR-140 at Deseret to the state highway system as SR-257. A short loop through downtown Hinckley, heading west from SR-140 on 2500 South and north on Main Street to SR-27, was added as State Route 240 in 1966 but dropped from the state highway system in 1969. With the deletion of SR-140 in 1969, SR-257 assumed its current extent, replacing the north–south piece of SR-140.
Major intersections 
- ^ a b "State Route 257 Highway reference". Utah Department of Transportation.
- ^ "Utah Highway Pages - 241 to 260". Stober, Daniel. Retrieved 1 April 2008.
- ^ "Designation of Secondary State Roads", Chapter 30, Session Laws of Utah, 1933: "(140) From Road 26 westerly via Oasis to Deseret thence to Road 27 at Hinckley."
- ^ "State Roads", Chapter 44, Session Laws of Utah, 1955: "Route 257. From Deseret on Route 140 southwesterly via Black Rock to Route 21 at Milford."
- ^ Utah Department of Transportation, Highway Resolutions: Route 240 PDF (1.28 MB), updated November 2007, accessed May 2008
- ^ Utah Department of Transportation, Highway Resolutions: Route 140 PDF (1.27 MB), updated November 2007, accessed May 2008
- ^ "State Highway Map". Utah Department of Transportation. Retrieved 1 April 2008.