Million Dollar Highway (US-550)

Between Ouray and Silverton — narrow cliffside curves through the San Juans with minimal guardrails, considered one of the most dramatic drives in the Rockies.

Length

25 mi

Sinuosity

1.6x

Turns/mile

Elevation gain

3,000 ft

Good to know

Best season: Late spring through fall
Typical speed limit: 30 mph
Surface: Narrow, exposed edges, avalanche closures possible in winter.

Source

Real, well-documented Colorado highway. Sinuosity/turns-per-mile computed from actual OSRM route geometry (matched within 6% of curated length).