James Island Marine State Park is a 581-acre, marine camping and moorage park with 12,335 feet of saltwater shoreline on Rosario Strait. Much of James Island has been designated a Natural Forest Area and is closed to public access, except for designated recreational areas and 1.5 miles of high bluff trails with extraordinary views.

The Wilkes Expedition named the island in 1841 to honor the earlier heroism of an American sailor, Reuben James. The federal government acquired the island and transferred it to the Washington State Parks and Recreation Commission in 1964.

A Discover Pass is required for vehicle access to Washington state parks for day use. For more information about the Discover Pass and exemptions, please visit the Discover Pass web page.

James Island has 13 campsites at three locations on the island. Camping is available on a first come, first served basis. Water Trail Site is on a hill above a pocket cove of the West Cove and has three campsites sites 11-13 and a pit toilet. These campsites are part of the Cascadia Marine Trail and are strictly reserved for use by boats arriving by human- or wind-powered watercraft.

The Saddle area spans from the West Cove shoreline across the island to the East Cove. There are six campsites sites 5-10, a picnic shelter and two picnic sites, composting toilet facilities, pay station, and moorage dock. A trail leads to the East Cove where there are four offshore mooring buoys. The loop trail system starts and ends here. The bottom structure at the West Cove is rocky and steeply sloped. It is not a good anchorage site.

The East Cove campground is a short walk from the Saddle area and has four campsites sites 1-4, one pit toilet, bulletin board, and pay station. From here, the loop trail leads southwest to the Water Trail campsites on the southwest side of the West Cove. Boaters moored in the East Cove are exposed to wakes from boat traffic in Rosario Strait.

There is no potable water on the island and no garbage service. Visitors need to pack-out what they pack-in. Boats may not use dinghies to reserve moorage space on the dock or buoys. Campers and boaters must self register and pay fees at the bulletin board / pay station. The nearest fuel and groceries are at Anacortes.