Trapper's Bay State Park, State park in Dickinson County, United States

Trapper's Bay State Park is a 57.5-acre (23.3 ha) park on the west side of Lake Park, Iowa, along the north shore of Silver Lake. Its Rustic-style picnic shelter has back and side walls of random rubble stone, a stone fireplace and chimney at the center of the back wall, and two round timber posts with bracing supporting a timber gable roof.

The park was established in 1933 when the Civilian Conservation Corps Company 778 constructed facilities under National Forest Service oversight. This work was part of New Deal programs that created jobs during the Great Depression and developed the region's infrastructure.

The park's picnic shelter, built in 1933–34 by Civilian Conservation Corps Company 778, is listed on the National Register of Historic Places. Its back and side walls are random rubble stone, with a stone fireplace and chimney centered on the back wall; two round timber posts with bracing carry the gable roof, and exposed purlins run below the overhang.

The park provides multiple access points to the water for fishing and recreation along the shoreline. The terrain is relatively flat and easy to walk, with ample parking and space for picnicking near the water's edge.

The randomly laid stone walls of the picnic shelter display 1930s craftsmanship where workers fitted each stone individually without precise patterns. This construction technique was typical of public works projects and makes the shelter a visible example of Depression-era engineering.