The Jefferson County Historical Society is located in downtown Madison, Indiana. It is housed in its Heritage Center which is directly adjacent to the historic Lanier Mansion. The mansion and other buildings were declared a National Historic Landmark District in 2006 (they are also a historic district on the National Register of Historic Places). The Heritage Center features exhibit on the Madison's early pioneer settlers, transportation, Victorian life, and the Civil War; special exhibits are offered as well. A research library is also housed in the Center, containing maps, genealogical records, government records, and photographs. The historical society manages the Railroad Station Museum (the station was constructed in 1895) and a 1918 caboose, both of which are on the Center's grounds.