Native Americans who lived here until about 500 years ago built the ceremonial mound complex at Crystal River. It was settled about 2,500 years ago when the river system and local marine estuary had matured and could provide enough food to sustain a large sedentary population. Throughout the site's occupation, social complexities and ceremonialism changed as populations increased. Although ideas and technologies from other areas filtered in and were adopted, these coastal dwellers retained much of their own cultural identity. Archaeological evidence shows the influence of at least three cultural periods at the Crystal River site.
Crystal River Archaeological State Park, a National Historic Landmark, is believed to be one of the oldest continuously occupied pre-Columbian sites in Florida, representing more than 2,000 years of settlement. A major ceremonial complex and burial site during the Deptford, Weeden Island and Safety Harbor periods, the Crystal River site has been the continued subject of archaeological study since the early 1900s.
The Crystal River archaeological site is made up of a group of shell middens, burial mounds and platform mounds. These features comprise a larger ceremonial complex of plazas and other landscape features. Two large platform mounds on the site are believed to have been used primarily for ceremonial purposes. Their size, structural uniformity and distinctive flat tops set them apart from the other mounds and middens at the site, denoting their special purpose.
Two vertical limestone slabs or 'stele' were discovered by former State Park Archaeologist Ripley Bullen in 1964 as part of an extensive archaeological survey of the park. The function of these slabs is uncertain although they appear to have been used as a type of marker. An astronomical connection has been suggested but not proven.
The museum at Crystal River Archaeological State Park was constructed in 1965 specifically to house artifacts recovered from the Crystal River site. The building was designed by Gainesville, Florida, architects Dan P. Branch and David Reaves in cooperation with Florida Park Service architect Warren A. Dixon.