Okmulgee Park is on land that was at the bottom of a vast inland sea 200 to 350 million years ago. The rocks at the park date back to the
Pennsylvanian Period. Okmulgee and neighboring
Dripping Springs Park are two of the very few places in the world where the rare
fossil,
Gymnophyllum wardi also known as "button coral", can be found. The facilities of Okmulgee and Dripping Springs Parks were constructed by the
Works Progress Administration and
Civilian Conservation Corps. The men of the WPA and CCC replaced an earthen dam at Okmulgee Lake which was built in 1927. They also built a
spillway and many of the park facilities that are still in use today. Both Dripping Springs and Okmulgee Parks became Oklahoma state parks when management of the park was transferred from the city of
Okmulgee to the state. The latter became Oklahoma State Park in 1963. Dripping Springs was leased to the state by the city in 1988. In 2015, the parks were removed from the state park system and are again managed by the City of Okmulgee. ==Recreation==