The 13 miles (19 km) from Idaho Springs to SH 5 forms about half of the Mount Blue Sky Scenic Byway.

Near Mestaa'ėhehe Pass, the highway heads west along the upper end of Echo Mountain Ski Area.

The highway then reaches an elevation of 10,000 feet at Echo Lake Park,[3] where it meets SH 5.

SH 103 terminates at Interstate 70 at a diamond interchange and the road continues as 13th Avenue through the neighborhood.

The segment east of Mestaa'ėhehe Pass was renumbered in 1954, and the route was entirely paved by 1956.