Twanoh State Park showcases Depression-era park architecture alongside Hood Canal’s warmest saltwater swimming in Union, creating Washington’s premier family-friendly marine camping destination. This 188-acre historic park combines Civilian Conservation Corps craftsmanship with abundant shellfish harvesting opportunities, making it one of the state’s most beloved and enduring recreational retreats since opening in 1923.
| Feature | Detail |
|---|---|
| Location | Union, Mason County, Washington |
| Address | 12190 E SR 106, Union, WA 98592 |
| Size | 188 acres |
| Coordinates | 47° 22’ 41.88″ N, 122° 58’ 36.83″ W |
| Established | June 9, 1923 |
| Key Features | 3,167 feet Hood Canal shoreline, National Register of Historic Places |
| Activities | Swimming, shellfish harvesting, camping, hiking, boating |
| Trail System | 2.5 miles of forested trails |
| Camping | 47 campsites (25 standard, 22 full hookup) |
| Hours | Summer: 6:30 AM to dusk, Winter: 8 AM to dusk |
Twanoh State Park holds the distinction as one of Washington’s oldest state parks, officially dedicated on June 9, 1923, making it the first state park purchased rather than donated. Built in the classic Civilian Conservation Corps style during the Great Depression, the park features remarkably preserved 1930s architecture that earned it National Register of Historic Places status in 2014. The park’s name derives from the Native American Twana tribes, also known as the Skokomish, who originally inhabited this Hood Canal shoreline.
The park’s 3,167 feet of saltwater frontage provides some of the warmest swimming waters in the Puget Sound region, while its 2.5 miles of inland hiking trails wind through towering old-growth forests along babbling Twanoh Creek. Historic springboard notches visible in trees throughout the woodland areas serve as reminders of the 1890s logging era that preceded the park’s establishment.
| Activity | Details | Season | Difficulty |
|---|---|---|---|
| Swimming | Warmest saltwater in Puget Sound region | Year-round | Easy |
| Shellfish Harvesting | Oysters year-round, clams August only | Seasonal | Easy |
| Hiking | 2.5 miles trails, 375 feet elevation gain | Year-round | Easy |
| Camping | 47 sites, reservable May 15 – Sept 15 | Year-round | Easy |
| Boating | Boat launch, 7 mooring buoys | Year-round | Easy |
| Tennis/Horseshoes | Court and pits available | Year-round | Easy |
Twanoh State Park offers comprehensive facilities anchored by historic Civilian Conservation Corps structures from the 1930s. The centerpiece is a large reservable kitchen shelter accommodating up to 150 people, available Monday through Thursday from May 15 to September 15, with year-round availability the rest of the week. A second kitchen shelter accommodates up to 40 people on a first-come, first-served basis. Three smaller covered kitchens provide water and electricity for day use visitors.
Additional amenities include 125 uncovered picnic tables, barbecue grills, fire circles, volleyball area, tennis court, playground, and horseshoe pits. The park features two restrooms with hot showers in the campground and three restrooms in the day-use area. A two-lane boat launch, boat dock, seven mooring buoys, and marine pumpout station support boating activities. The historic concession building now houses The Posh Pescatarian restaurant, serving freshly prepared dishes with beer and wine from 11 AM to 7:30 PM daily.
The main campground offers 25 standard campsites and 22 full-hookup sites accommodating RVs up to 35 feet long. Campsites are reservable between May 15 and September 15, available first-come, first-served the remainder of the year with limited winter water supply. As part of the Cascadia Marine Trail system, one waterfront primitive campsite serves visitors arriving by kayak or other non-motorized watercraft on a first-come, first-served basis.
Packaged firewood is available for purchase from the campground host, as gathering firewood on park property is prohibited. The campground operates year-round with two restroom facilities and shower access nearby.
A Discover Pass is required for day visits to Twanoh State Park, with annual passes available for $45 and daily passes for $10. For watercraft launching, visitors need either a Natural Investment Permit or combination of a Discover Pass and daily launch permit, available for $7 at the park. The launch docks are removed during winter months for seasonal maintenance.
Shellfish harvesting requires a recreational fishing license from the Washington Department of Fish and Wildlife. Clam and mussel seasons typically open August 1-31, while oyster harvesting remains open year-round. Oysters must be shucked on the beach with shells left at the same approximate tide height where collected. The best oyster harvesting occurs at the west end near the boat ramp, while clams are found in a narrow band below the oyster beds from the boat ramp to the eastern park boundary.
Twanoh State Park continues its century-long legacy as Hood Canal’s premier family destination, where Depression-era architecture meets modern recreational amenities in one of Washington’s most historically significant and naturally beautiful settings.
Twanoh State Park is a 188 acre marine park on Hood Canal in Union, known for some of the warmest saltwater swimming in Washington. Opened in 1923, it features Civilian Conservation Corps architecture, a long stretch of Hood Canal shoreline, and popular shellfish harvesting.
Yes, in season. Twanoh is a well known spot for harvesting oysters and clams along Hood Canal at low tide. Always check the current Washington shellfish safety closures and seasons before you gather, since they change through the year.
Yes. The park offers campsites near the water along with picnic areas and a swimming beach. It is a favorite family destination in summer, so reserve through Washington State Parks, especially on warm weekends.
Yes. A Washington State Discover Pass is required for day use parking at Twanoh State Park. Camping fees cover your vehicle overnight, so a separate day pass is not needed while you are staying.
Twanoh sits on a shallow, protected reach of Hood Canal that warms up in summer, making its saltwater among the warmest for swimming in the state. The gentle beach and calm water are a big part of why families have loved this park for a century.
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The Washington State Parks Directory covers all 146 state parks across Washington — from saltwater shores and mountain meadows to ancient lava tubes and desert canyons. Find trails, camping, activities, and detailed visitor information for every park in the state.
Browse All Washington State ParksThe day-use area will be closed July 5 - Aug 31, 2026 for shoreline and creek restoration. The main parking lots, beach, pier, dock, kitchen shelters and day use restrooms will also be closed. The Posh Pescatarian concessionaire will remain open with parking available for customers in the north parking lot. The campground will operate on a first-come, first-served basis throughout the closure. Campers may hear construction noise, including at night, during the duration. Camping reservations will reopen if construction ends early. View the full closure alert here. Переглянути повне сповіщення про закриття українською мовою. Consulte la alerta de cierre completa en español.
Reservations for campsites at Twanoh State Park are closed starting June 1, 2026 through spring of 2027 for a shoreline restoration project. Specific dates and details will be published when available.
Twanoh does not have trash service in day-use areas. Pack it in, pack it out! That includes food scraps, wrappers and recyclables. Additionally, please unbox and recycle new gear and gadgets at home – packaging is one of the biggest contributors to in-park litter. Thank you for helping reduce waste, protect wildlife and keep our parks beautiful for years to come.