High Quality Content by WIKIPEDIA articles! 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 had military significance in conflicts up 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. From the tower`s roof, visitors can also get a great 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 since 1924. It was opened to the public in 1963.