The Western Brook Pond in the Gros Morne National Park is a fjord which has become separated from the sea -- so is now technically a lake. There is a 3km walk in from the main road to the lake (Newfoundlanders say pond, rather than lake). We then take a boat tour for a couple of hours. The lake is deep and long, some 16km long -- but has very little fish or other life because of the cold conditions. There has been very little human development in the area, so it is pristine. The water is exceptionally pristine, as a result.