Lizard Mound Park is one of the best preserved and most diverse prehistoric effigy mound archeological sites in the state, containing numerous mounds dating from A.D. 650 to 1300 in conical, linear, bird, panther, and lizard shapes. Originally known as the Hagner Indian Mounds, it was established as a state park in 1950 and renamed for the park's most unique mound. It was entered into the National Register of Historic Places on October 15, 1970, and in 1986 Washington County acquired the park, which includes a mile-long marked nature trail around the mounds.