Cranberry Lake is the freshwater half of the West Beach area at Deception Pass State Park, Washington's most visited state park. A low ridge of dunes is all that separates the lake from the Strait of Juan de Fuca, so you can wade in cold salt water on the West Beach side and then walk a few hundred feet to swim in a lake that actually warms up in July. The roped swim beach is on the lake's northwest corner, a sandy strip with a lawn behind it, picnic tables, a bathhouse with restrooms, showers and changing rooms, and a summer kayak and paddleboard rental stand. There are no lifeguards. The lake bottom is sandy near the beach and grows lily pads toward the middle, and the water is dark, calm and shallow enough near shore for small kids.

The Civilian Conservation Corps built the West Beach and Cranberry Lake facilities in the 1930s, and the bathhouse and picnic shelters are listed as a historic district. The CCC Interpretive Center at Bowman Bay, across the bridge on the Fidalgo Island side, tells that story. The Sand Dunes Interpretive Trail, an easy 0.8-mile loop with an observation deck over Rosario Strait, starts from the same parking area.

Only human-powered and electric boats are allowed on the lake, and there is a $7 launch permit for private watercraft. The lake is stocked with trout and the rocky east shore is the fishing side. The Cranberry Lake campground, the park's biggest, sits between the lake and North Beach; its Forest Loop and lower loops reserve through the state parks system and some loops close in winter. Day-use parking requires a Discover Pass, $10 for the day or $45 for the year, sold at the pay station in the lot; campground parking is covered by the camping fee. The park is open 6:30 a.m. to dusk in summer and 8 a.m. to dusk in winter. Dogs are welcome on leash but not in the swim area.

A few things to know for 2026: the West Beach lot is closed to vehicles over 25 feet, so trailers and motorhomes need to park elsewhere in the park, and the northeast corner of the dunes trail is closed for storm damage. Pass Lake, on the Fidalgo side, has had algae closures; check the park page before you go.

Deception Pass State Park covers 3,854 acres on both sides of the pass, and the 1935 bridge, the tidal rapids under it, and the trails to Goose Rock and Lighthouse Point are the reasons most of the park's visitors come. The Cranberry Lake beach is the quiet place to end a day of all that. Oak Harbor is nine miles south on SR 20 and Anacortes about the same distance north.