Colgin Hill is a historic house in Gainesville, Sumter County, Alabama. The one-story structure began as a log dogtrot house for William Colgin in 1832. The breezeway was enclosed, creating a center hall, and Greek Revival details added within a couple of decades of the initial construction. It serves as an example of the transition in Alabama from the frontier to a more refined society. Historians consider it to be the oldest extant building in Gainesville. It was added to the National Register of Historic Places on October 3, 1985.