About Keystone Harbor
Operated as part of Fort Casey State Park. Fort Casey State Park (including Keystone Spit) is comprised of 411.46 acres with 7,000 feet of freshwate frontage and 110,810 feet of saltwater shoreline on Admiralty Inlet.
Recreation AreaRecreation.gov
Keystone Harbor
Coupeville, Washington · Island County
Operated as part of Fort Casey State Park. Fort Casey State Park (including Keystone Spit) is comprised of 411.46 acres with 7,000 feet of freshwate frontage and 110,810 feet of saltwater shoreline on Admiralty Inlet.
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48.17080, -122.67094
Open in OpenStreetMap5-Day Forecast
Weather at Keystone Harbor
Live forecast for the park. Plan your visit accordingly.
Today
Overcast
70°/56°
💧 3%🌬 19mph
↑ 5:37 AM ↓ 8:56 PM
Sun
Light Drizzle
64°/57°
💧 17%🌬 12mph
↑ 5:39 AM ↓ 8:54 PM
Mon
Overcast
68°/56°
💧 2%🌬 12mph
↑ 5:40 AM ↓ 8:53 PM
Tue
Overcast
68°/55°
💧 6%🌬 14mph
↑ 5:41 AM ↓ 8:52 PM
Wed
Overcast
64°/55°
💧 3%🌬 14mph
↑ 5:43 AM ↓ 8:51 PM
Forecast data © Open-Meteo. Refreshed every 6 hours. Always check the most recent forecast before heading out.
How to Get There
Located on Highway 20, 3 miles south of Coupville on Whidbey Island, Island County, Washington.
Driving directions (Google Maps) →Plan Your Visit to Keystone Harbor
Heading to Keystone Harbor? A few things to know before you go:
- Reservations: popular sites fill up fast — check Recreation.gov 6 months in advance
- Fees: day-use and camping fees vary; check current rates on the official park page
- Trash & pack-out: follow Leave No Trace principles
- Wildlife: store food in bear boxes where provided; never feed wildlife
- Weather: the 5-day forecast above is updated every 6 hours; verify just before you go
References & Official Resources
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