Southwest Alaska includes a huge, complex, and relatively unknown swath of terrain. It is over from the western Bering Sea coast to Cook Inlet. Although much of the region is coastal, it also includes tens of thousands of square miles of interior boreal forests, swamps, and highlands, and the immense mountain barrier of the southern Alaska/Aleutian Range. The Aleutian Range, part of the Ring of Fire, includes many of Alaska's volcanoes including Mount Katmai, Novarupta and the Valley of Ten Thousand Smokes, Mount Redoubt, Mount Iliamna, and Augustine Volcano.