Blake Island Marine State Park is a boat-in campground with 44 standard campsites, three Cascadia Marine Trail sites for paddlers, and moorage docks with electrical service and buoys on a first-come, first-served basis (3-night limit).

The island offers 5 miles of saltwater beach, 8 miles of hiking trails, and excellent wildlife viewing, though it operates on a strict pack-it-in, pack-it-out policy with no trash service.

Access is water-only via private boat, kayak, paddleboard, or tour ferry from Seattle, with peak-season reservations available May 15-September 15.