Harmony Museum, on the Diamond in the town center, offers guided tours of an 1809 warehouse, an 1811 Harmony Society building and an 1830s Mennonite family log house. The Harmony Society was founded in 1804 by German Lutheran Separatists. Exhibits showcase the 1815 Mennonite resettlement, Delaware Native American history and Maj. George Washington's 1753 military mission to the area. Target and hunting rifles made by 19th-century gunsmith Charles Flowers also are displayed. Two cemeteries and Rapp's Seat, a seat carved into a rock used for meditation, are on the grounds.
Visitors can add guided tours of a nearby historic barn or meetinghouse onto the guided museum tour with advance notice and for an additional fee.