Canada is located in the northern part of the North American continent and it extends from the Atlantic to the Pacific and northward into the Arctic Ocean. Canada is the world's second-largest country by total area, and its common border with the United States is the world's longest land border shared by the same two countries. Since the end of the last glacial period, Canada has consisted of eight distinct forest regions, including extensive boreal forest. Canada has over 30,000 large lakes, more than any other country, containing much of the world's fresh water. There are also fresh-water glaciers in the Canadian Rockies and the Coast Mountains. Canada is geologically active, having many earthquakes and potentially active volcanoes, notably Mount Meager, Mount Garibaldi,Mount Cayley, and the Mount Edziza volcanic complex.