Shastina is a satellite cone on Mount Shasta’s western flank and the second youngest of the four overlapping cones that form the mountain, the Cascade Range’s most voluminous stratovolcano. Rising 12,335 feet, it would rank among the higher Cascade volcanoes if it stood apart, though it is often omitted because it is attached to Shasta. It formed around 7650 BC during a VEI-4 eruptive episode that also affected Shasta’s summit and Red Banks. Its smooth cone is broken by Diller Canyon, a huge west-side cleft formed by pyroclastic flows and erosion, and its summit crater contains three of the highest subaerial lakes in the Cascades.