Posey Island Marine State Park
An itty-bitty island hides in plain sight, between Pearl Island and Roche Harbor in the San Juan archipelago.
Posey Island Marine State Park is popular with kayak groups and porpoises, but, depending on the day, you may also have the place to yourself.
Though Posey seems barren at first, a thorough perusal reveals meadow grasses, ancient Yew trees, bright orange lichen and wildflowers blooming in season. Photographers and painters have found endless creative opportunities here.
Ready for a hard paddle? Take your kayak for a spin around Spieden Island and its neighboring rock formations. Look for antelopes and longhorn sheep on savannah-like Spieden Island, once a game park. Though you cannot land on the privately owned island, wildlife is often visible from the water.
At the end of the day, retire to one of Posey Island's two group campsites, each with a sweeping view. Grill up a hearty meal, sit back for a big-sky cloud show or a glorious sunset and enjoy a rare opportunity to do nothing but rest.
Posey Island Marine State Park is a 1-acre marine camping park with 1,000 feet of shoreline. It is located a quarter mile north of Pearl Island, near Roche Harbor, San Juan Island. Posey Island is part of the Cascadia Marine Trail. There is no potable water on the island, and visitors must pack out what they pack in. Camping reservations are required for both campsites, which are for the exclusive use of boaters arriving by human- or wind-powered watercraft.
A paddle around the northwest side of Spieden Island should not be attempted during tidal shifts, as the waters are unpredictable and dangerous.
Please do not approach rock formations where harbor seals are resting; their undisturbed naps out of water are critical to their health and safety.
Picnic & day-use facilities
Visitors arriving by vessels with motorboats are not permitted to camp at the park, but may use the island for day use. There is no potable water or garbage service to the island. Visitors must pack out what they pack in. There is one composting toilet.
Orca whales are often seen in the waters near this island. There are no mooring buoys or docks. This is primarily a kayaking site. The site is heavily used by commercial kayak tours as a rest stop during whale watching tours in nearby waters.
Posey Island has two campsites that are part of the Cascadia Marine Trail (PDF). Campsites may be reserved, May 15 - September 30, with 14 days minimum notice. To reserve a campsite, call 360-378-2044 (Lime Kiln Point State Park). We begin accepting reservations on January 2 at 9 a.m. for each calendar year.
All campsites are for the exclusive use of boaters arriving by human or wind-powered watercraft. Each campsite can accommodate a maximum of eight campers. This maximum number of campers is strictly enforced due to the small size of the island. No exception. Paddlers and sailors must be prepared to seek other campsites if the campsites are at capacity. Reservations:
- Reservations for Friday or Saturday nights May 15-September 30 are limited to one site and one night per reservation. Reservations are also limited to a total of any five Friday and /or Saturday one-night reservations per month.
- Reservations for Sunday - Thursday nights May 15-September 30 are limited to one site and a maximum of two nights per reservation. Reservations are also limited to a total of six one- or two-night weekday reservations per month.
Campsites are available on a first-come, first-served basis May 15-September 30 on nights when they have not been reserved. No reservations are needed October 1- May 14.
For fee information, check out our camping rates page.
Posey Island Marine State Park became a state park in 1960 under lease from the United States Bureau of Land Management.