Driving Roads / Million Dollar Highway

The roughly 25-mile Ouray-to-Silverton stretch of US-550 climbs over 11,000-foot Red Mountain Pass with sheer drop-offs and famously few guardrails. It runs about 25 miles along US-550 (Ouray to Silverton) in Colorado. Drive time: about 50 minutes one way.
Best time to go: Late spring to early fall for dry pavement. The road stays open in winter but avalanches are frequent and can block it, and the 8% north side is treacherous in snow.

Sources: Length · High point · Best time. Drive time is the route time for the mapped route without stops, from Mapbox.
Record the cliff-edge pass crossing and keep it in your drive log with the time and distance. A careful-cornering road where smoothness beats speed.
Narrow lanes, steep grades and big drop-offs with limited guardrails demand low speeds, full attention, and extra caution in rain or snow.
Open Road keeps every drive: the route on a map, the time and the distance. On iPhone and Android.