North America, the 3rd largest continent, includes Canada, Greenland, Mexico, the United States, all the countries of Central America and the island countries and dependencies of the Caribbean. The continent's (highest point) is Mt McKinley, in Alaska, at 20,322ft (6,194m), while the (lowest point) is Death Valley in California, at 282 ft (86m) below sea level. Map of major landforms here.