The lagoons are shallow bays between rocky headlands where coastal wave action has formed a sandy bar separating each lagoon from the ocean.[1] The 2,256-acre (913 ha) park was established in 1931.[2]
Dry Lagoon, at the southern end of Stone Lagoon, is separated from Stone Lagoon by what may become an island if the sea level rises. Dry Lagoon is presently a wetland representing natural conditions of similar land used for a sawmill near Big Lagoon, or converted to agricultural purposes around the estuaries of Redwood Creek to the north and Little River to the south.