Posey Island is a small park located right next to Roche Harbor, and it is part of the Cascadia Marine Trail. Although perhaps not a destination in itself, Posey makes a welcome place to stay when making longer trips around the area, specifically those making the trip to Stuart Island and the Gulf Islands. Campsites can be reserved throughout the summer, and because of the small size of the island the maximum number of campers is strictly limited to 16 people. Because of its close proximity to Roche Harbor, the island can attract party-goers during the summer months, but in the fall and winter it offers a nice bit of solitude. Like many of the islands in the San Juans, kayakers often have the entire island to themselves in the off-season.