Upper Tampa Bay Park on the Double Branch Peninsula near Oldsmar is both a protected natural area and an important archaeological site in the Tampa area. Its light development reflects the fragility of the surrounding environment. Within it, the Upper Tampa Bay Archeological District was added to the National Register of Historic Places on December 10, 1985. The area was inhabited by the Tocobaga from about 900 A.D. until the 1500s, and their shellfish mounds show long-term use of the shoreline. The park also includes Double Branch Creek, supports wildlife such as redfish, snook, dolphins, manatees, and otters, and offers modest nature-oriented recreation.