Lassen Volcanic National Park is where the Sierra gives way to the Cascades in northern California. It is a wonderful volcanic landscape with boiling sulphur pools, cinder cones, fumaroles, and volcanos. Lassen Peak, the southern most and still active volcano, is the centerpiece to this small park. As with all Cascade volcanoes, it is often at its very best with a fresh layer of snow, as is the entire park. It is one of the prettiest areas to visit in winter.