Original: The Cascade Volcanoes (also known as the Cascade Volcanic Arc or the Cascade Arc) are a number of volcanoes in a volcanic arc in western North America, extending from southwestern British Columbia through Washington and Oregon to Northern California, a distance of well over 700 mi (1,100 km).
Simplified: The Cascade Volcanic Arc (also known as the Cascade Volcanoes or the Cascade Arc) is a major range of volcanoes in southwestern British Columbia, Washington, Oregon and in northern California.