Marblemount is a census-designated place in Skagit County, Washington, United States.

Present-day Marblemount was the site of an indigenous village when naturalist George Gibbs explored the region in 1858.

A community of Euro-Americans arose in the 1870s to supply goods for miners along the Skagit and Cascade River drainages.

Marblemount is on Washington State Route 20, the North Cascades Highway, often rated as the top motorcycling road in Washington State for scenery, remoteness, road quality, and other features.

It is the last place for road services on the west side of North Cascades National Park for eastbound travelers, the next being Winthrop, 70 miles (110 km) away.