The name, Mammoth TUFF, is a nod to the Long Valley Caldera and the volcanic stone that defines ‘gravel’ in the area. The caldera was formed about 760,000 years ago in a volcanic eruption from which the magma still underlies it, heating underground water and fueling hot springs the event will ride by. The short course will circle the famous caldera. The medium and long courses travel through the Volcanic Tableland formed by the Long Valley Caldera. Prepare to be transported back in time.