The elevation of the forest ranges from about 1,500 feet (460 m) above sea level on the western edge of the forest to almost 10,500 feet (3,200 m) at the top of Mount Jefferson, Oregon's second highest peak. Seven major peaks of the Cascades—Mount Jefferson, Mount Washington, Three Fingered Jack, Diamond Peak, North, Middle and South Sisters—as well as numerous high mountain lakes are within these wilderness areas. The McKenzie River and the North Fork Middle Fork Willamette River are Wild and Scenic rivers.