Carleton Martello Tower in Saint John, New Brunswick, is one of the nine surviving Martello Towers in Canada. The tower dates from the War of 1812 and played a significant role in conflicts until the Second World War. The site now features a restored powder magazine, a restored barracks room, and exhibits in the tower and in the visitor centre. The tower's roof offers a view of the city of Saint John and its harbour. Carleton Martello Tower is the oldest building in the city and has been designated as a National Historic Site of Canada since 1930. It was opened to the public in 1963.