Site of a large naval dockyard and research centre, Halifax's sister city has a pleasant waterfront with shop-lined streets descending to it. Because of the presence of 23 lakes within its city limits, Dartmouth is called the City of Lakes. Settled in 1750, it attained official town status in 1873. Growth was gradual until the construction of the Angus L. MacDonald Bridge in 1955. The 1970 A. Murray MacKay Bridge, at the mouth of the Narrows, spawned additional development. Connected to Halifax by two bridges, Dartmouth is serviced by the oldest continual saltwater ferry service in North American.