Located on the Bay of Islands at the mouth of the Humber River, the city is the second-largest population centre in the province behind St. John's, and smallest of three cities behind St. John's and Mount Pearl. As such, Corner Brook functions as a service centre for western and northern Newfoundland. It is located on the same latitude as Gaspé, Quebec, a city of similar size and landscape on the other side of the Gulf of St. Lawrence. Corner Brook is the most northern city in Atlantic Canada.