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 .