Ha Ha Tonka State Park

Ha Ha Tonka State Park
"Castle" ruins at Ha Ha Tonka
Location in Missouri
Ha Ha Tonka State Park (the United States)
LocationCamden County, Missouri, United States
Coordinates37°58′27″N 92°45′47″W / 37.97417°N 92.76306°W / 37.97417; -92.76306
Area3,751.74 acres (1,518.28 ha)
Elevation804 ft (245 m)
Established1978
Administered byMissouri Department of Natural Resources
Visitors543,406 (in 2022)
WebsiteOfficial website

Ha Ha Tonka State Park is a public recreation area encompassing 3,751 acres (1,518 ha) on the Niangua arm of the Lake of the Ozarks, about five miles south of Camdenton, Missouri, in the United States. The state park's most notable feature is the ruins of Ha Ha Tonka, an early 20th-century stone mansion that was modeled after European castles of the 16th century.

The park also features caves, sinkholes, and bluffs overlooking the lake. It is a prominent example of karst topography, which is geological formation shaped by the dissolution of a layer or layers of soluble bedrock. A 70-acre (28 ha) portion of the park was designated as the Ha Ha Tonka Karst Natural Area in 1981.