Mercersburg Borough was incorporated in 1831 with a population of 700. The Borough Hall sits on a lot that was the site of the first Town Jail and an early band shell.
F. Keagy built Borough Hall in 1904 for $4,304.38; G. Seylor added the clock Tower in 1909 for $375.00. The south end housed the Eclipse Fire Engine until 1924 and the Police Department since the late 1920's. The second floor housed the library 1927-1973 and the office of the District Office since 1979