05 reviewsSelect a month, then check for open campsites
Price
Varies
Booking
Reservable
Sites
2 campsites
Season
Year-round
Cell
Unknown
Pets
Check Policy
Select a month, then check for open campsites
Price
Varies
Booking
Reservable
Sites
2 campsites
Season
Year-round
Cell
Unknown
Pets
Check Policy
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Learn more about alerts →Posey Island Marine State Park
48.6188, -123.1681
Kayakers after a classic San Juan Islands overnighter will find good gravel beach landings, dark skies, and sunset views across the Salish Sea. Early fall is the sweet spot: calmer water, fewer commercial tour groups, and still solid wildlife. Grab a reservation fast since only t
No potable water means hauling everything in, and with only two sites, summer weekends can feel overrun by commercial kayak tours stopping through. Anyone who needs cell service, a flush toilet, or a motorboat to get there has the wrong campground.
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Early fall delivers the best conditions. Daytime highs run mid-50s to mid-60s°F (12–18°C), with cool evenings and calmer seas than summer. Boat traffic drops after Labor Day, and wildlife viewing stays strong through September and October. Clearer skies improve paddling and photography before winter storms arrive. Summer brings more visitors and wind. Check marine forecasts and tides before any trip. The island's exposure makes conditions variable.
Early fall cited as best: calmer seas, cooler temps, and less day‑boat traffic.
Reservation tips, booking windows, and free cancellation alerts.
Very limited developed amenities. One composting outhouse; no potable water, no showers, no hookups, and no garbage service. Two primitive group campsites with minimal infrastructure (some sites have picnic table and fire ring). Pack in/pack out required.
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