|Maintained by UDOT|
|Length||69.246 mi (111.441 km)|
|South end||SR-21 in Milford|
|North end||US 6 / US 50 in Hinckley|
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.
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.
|Beaver||Milford||0.000||0.000||SR-21 (Center Street)||Southern terminus|
|Millard||Hinckley||69.246||111.441||US 6 / US 50 - Ely, Salina, Provo||Northern terminus|
|1.000 mi = 1.609 km; 1.000 km = 0.621 mi|
(140) From Road 26 westerly via Oasis to Deseret thence to Road 27 at Hinckley.
Route 257. From Deseret on Route 140 southwesterly via Black Rock to Route 21 at Milford.