Fort Lonesome is a rural area located in southeastern Hillsborough County, Florida, United States, southeast of Tampa. A sawmill briefly revived the area with a few houses and three stores in the early 1930s. It was short-lived: a fire destroyed the mill and eventually the "town" disappeared. Today, it is mainly a farming region.
Fort Lonesome is located at the intersection of State Road 674 (Ruskin-Wimauma Rd) and County Road 39S, the site of a gas station and power substation.
The community is served by Hillsborough County Schools.