The Roberts Island complex is an archaeological site in Citrus County, Florida, near the Gulf of Mexico, dating from the late Woodland period. It is located on an island in the Crystal River midway between the springs at the head of the river and the mouth of the river on the Gulf of Mexico. The site is a geographically separate unit of the Crystal River Archaeological State Park. The site includes three shell mounds and three middens. Two of the mounds may have had stepped sides. The Roberts Island complex was developed as the Crystal River site declined and most other ceremonial sites in the region were abandoned during the 7th or 8th century.