Many parts of the park and surrounding area are accessible by bicycle.
In Stehekin, the Stehekin Valley Road is open to cyclists to three miles above High Bridge but is unpaved beyond Harlequin Campground. Space for bikes can be reserved on the ferry or bicycles can be rented from in Stehekin. The also includes built-in bicycle racks.
In the Methow Valley, the Okanogan-Wenatchee National Forest offers opportunities for and mountain biking.
Other roads, including the Cascade River Road and SR 542, are also at least partially accessible by bicycle. Check the road condition pages for the national park and the Mt. Baker-Snoqualmie and National Forests for current information on these and other roads.