U.S. Route 285 (US 285) is the section north-south highway in Colorado that starts at the New Mexico state line and ends at I-25, US 87, and SH 30 in Denver.

Heading north from the Colorado border, US 285 passes through the main part of the San Luis Valley, eventually reaching Alamosa.

The highway brushes Salida and follows the Arkansas River north up the valley, then takes a sharp eastward turn just before the small town of Buena Vista.

On March 14, 2008 both houses of the Colorado legislature, in a unanimous vote, named the section between Kenosha Pass and C-470 the Ralph Carr Memorial Highway.

[2][3] The short segment between US 50 at Salida and US 24 at Buena Vista closely parallels the original U.S. Route 650,[4] which was designated in 1926, but eliminated in 1936 when US 285 was commissioned along its present extent from Sanderson to Denver, mostly replacing state-numbered highways.