Colorado State Highway 257

State Highway 257
Map of Weld County in northern Colorado with SH 257 highlighted in red
Route information
Maintained by CDOT
Length:	18.478 mi (29.737 km)
Major junctions
South end:	SH 60 in Milliken
	US 34
North end:	SH 14
Location
Counties:	Weld
Highway system
Colorado State Highways Interstate U.S. State Scenic ← SH 239 SH 263 →

State Highway 257 is an 18.478-mile-long highway in Colorado's Front Range. It is located entirely in Weld County. Its western end is at SH 60 and its eastern end is at SH 14.

The route begins at SH 60 in the western part of Milliken, a town in central Weld County. It then heads northward, crosses the Big Thompson River, a tributary of the South Platte River then enters Greeley.

At Greeley, SH 257 has two interchanges with US 34 and US 34 Business. Because the intersection is so close to the terminus of Business Route 34, the two interchanges are just 0.3 miles apart. Both are diamond interchanges, but at US 34 there are only entrance ramps from the east side.

It then heads northward, and begins to curve northwest over the Cache la Poudre River and into Windsor. It intersects State Highway 392 and abruptly turns west, beginning a concurrency at Main Street; about a mile later SH 257 abruptly turns back northward at 7th Street, ending the concurrency. It then heads all the way north to State Highway 14, where it terminates. No towns exist on the route from Windsor to SH 14.