The Cascade Range is a chain of mountains that extends between Lassen Peak in northern California and the Fraser River in southern British Columbia, Canada. The range is about 700 miles (1,100 kilometers) long. The range lies about 100 to 150 miles (160 to 240 kilometers) inland from the Pacific Coast.
The most famous mountains in the Cascades are volcanoes. Two of them erupted in the 1900′s. Mount St. Helens, in Washington, erupted frequently between 1980 and 1986. Lassen Peak, in California, last erupted in 1917.
The Cascades began forming about 240 million years ago. Rainfall is heavy in the Cascade Range. The range has deep valleys that are covered with heavy fir and pine forests.