Fort Foster State Historic Site is part of Hillsborough River State Park, though located on the East Side of US 301 from the park. Fort Foster State Historic Site is a reproduction of a fort originally built on the same grounds in December 1836, by Col. William S. Foster and his 430 men. During the Second Seminole War the purpose of Fort Foster was to defend the bridge crossing at the Hillsborough River and act as a resupply point for the soldiers in the field. The fort was garrisoned on and off from December, 1836 – April, 1838. Although the fort was attacked on several occasions, the worst attack occurred in February 1836, when a small group of Seminoles attempted to set fire to the bridge. The attempt was thwarted by aggressive musket and cannon fire from the fifty or so U.S. Navy sailors and the 20 artillery men within the fort.