To find the trailhead, drive south for about 2.5 miles on a dirt road that begins immediately after the parking area for Bunchgrass Overlook. At the beginning of this road and to the west is an old cinder cone called Hippo Butte. After about 2.5 miles, there is a small turnout on the west side of the dirt road that is the parking area for the trail. The trailhead is easily located at about the midway point of the turnout. Follow the trail to where it ends at the rim of Mammoth Crater.
Mammoth Crater and Modoc Crater are responsible for about 70% of the lava flow in the park. The lava that flowed from both of these craters is also responsible for the majority of lava tube caves found in the park. Mammoth crater once contained a massive lake of lava that overflowed instead of erupted, leaving behind the empty crater. The lava from this crater was highly fluid and traveled all the way to the northern part of the park, creating lava tube caves all along the way.