The southern terminus of SR 257 is at its intersection with SR 195 northeast of Jasper. From this point, the route takes a northeasterly course as two-lane undivided Curry Highway, passing through wooded areas with some homes.
The northernmost point of SR 257 is situated at its junction with SR 195 northeast of Jasper. From this location, the route moves in an easterly northerly direction as part of the two-lane Curry Highway, passing through wooded zones and individual dwellings.