The state park is covered by an evergreen forest that surrounds a crater lake of volcanic origin.

[2] The park is the site of a 400-foot (120 m) volcano in the Boring Lava Field where a magma-induced steam explosion 105,000 years ago[4] made a large bean-shaped crater, a maar, which later filled with water, forming a crater lake.

[5] The lake was the site of a resort dating from the 1920s when a consortium of businessmen planned an upgrade that would include the addition of a dance hall, "swimming tanks," and amusements plus a power plant and electric lights.

[10] The park includes a swimming area, boat launch, campground, and cabin rentals.

Largemouth bass, grass carp, and crappie are present, with trout fishing the main attraction for anglers, especially on opening day.