Detillion Campground is a boat-in only campground on the Spokane River Arm of Lake Roosevelt with 12 primitive tent sites, a boat dock, and vault toilets—making it the largest boat-in campground in the area with direct water access.

Located upstream from Ponderosa Campground, it provides convenient access to the Fort Spokane Visitor Center and surrounding trails via short boat rides.

The campground operates on a first-come, first-served basis and is free to use, though a boat launch permit is required at developed areas.