Small red cinder cone perched on the west wall of Long Valley Calde...

The basaltic cone was erupted more than 64,000 years ago. The steep slope that cuts through the middle of the photo is the western caldera wall; the relatively flat ground in lower right is the west floor of the caldera. The layers of rocks exposed in the caldera wall above the cinder cone are among the oldest volcanic rocks in the area--they were erupted between 3.6 and 2.2 million years ago.