Lunar Crater Volcanic Field lies about halfway between Tonopah and Ely, Nevada along US Highway 6. The Field is about 135 km east of Tonopah. The Field is named after Lunar Crater, a phreatic pit in the southeast quadrant of the Field. The phreatic eruption formed the crater when magma came in contact with ground water in the pre-existing rocks near the Earth's surface. Lunar Crater is the only phreatic feature in the Volcanic Field. The other volcanic features are cinder cones and lava flows.