Vulcan is the largest of the six volcanoes in the Albuquerque volcanic field on the West Mesa near Albuquerque, New Mexico. An inactive spatter cone in the Rio Grande rift, it was built by lava fountains from a central vent and smaller flank vents, rising about 600 feet above the valley floor. Its arches, caves, crater lava pond, preserved lava tubes, and layered slopes reveal how molten lava cooled, welded, and spread, with wind likely shaping the thickest deposits. Believed to have last erupted around 150,000 years ago, it is dormant, though the region still shows slow uplift above the Socorro Magma Body. From 1951 to 1973, a large J on its eastern slope gave it alternate names.