Potholes State Park is a 640-acre camping park with 6,000 feet of freshwater shoreline on Potholes Reservoir (also known as O'Sullivan Reservoir). Potholes Reservoir is often confused with the Pothole Lakes themselves, which are a 30- to 45-minute drive from the park. The terrain is desert with freshwater marshes.
Located 17 miles southwest of Moses Lake, Wash., just east of the Cascades in Grant County.
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