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San Juan Islands

Posey Island State Marine Park

Holding: Fair
Shelter: Fair
2 mooring buoys
Shore access
Anchorage Pacific Northwest

About This Anchorage

Posey Island may be the smallest state park in Washington — barely an acre of land at high tide — but it punches well above its weight as a destination. Just a quarter-mile off the coast of San Juan Island near Roche Harbor, Posey offers a primitive campsite for one or two small boats and a pair of mooring buoys. It's the definition of a 'blink and you miss it' anchorage, perfect for couples looking for an intimate wilderness experience minutes from Roche Harbor's amenities.

Highlights

  • Washington's smallest — and most intimate — state marine park
  • Just 0.25nm from Roche Harbor for provisioning and fuel
  • Primitive camping on the island for 1–2 boats
  • Spectacular sunsets over Spieden Channel
  • Wildlife: harbor seals haul out on surrounding rocks

Cautions & Notes

  • Only 2 mooring buoys — no anchoring room if buoys are taken
  • Exposed to west and north — uncomfortable in NW blow
  • Tidal current through Spieden Channel can be strong
  • Very small island — no fresh water, no facilities beyond a fire ring

Location

Posey Island State Marine Park

48.6215°N, 123.1549°W