El Malpais is Spanish for "the badlands," a name that perfectly describes this region of New Mexico, where countless volcanic eruptions sent rivers of molten rock and flying cinders over what is now a bleak valley of three million years' worth of hardened lava. Native American settlers probably witnessed the last of the eruptions. Their former home is now a land of craters and lava tubes, cinder cones and spatter cones, ice caves and pressure ridges, and a surprising amount of vegetation. Even on terrain that one would presume to be barren, wind-deposited debris has thickened enough to support grasses, cacti, aspen, pine, juniper, and fir. Preserved as El Malpais National Monument (managed by the NPS) and Conservation Area (managed by the BLM), two Wildernesses lie within the boundaries of BLM land: Cebolla and West Malpais. The latter Wilderness is home to Hole-In-The-Wall, the largest islandlike depression in these lava fields. Over the years, moisture and soil collected on some of the oldest lava to form this 6,000-acre park of ponderosa pine. Be prepared for heat and high winds. Some hikers escape a fierce dry wind cutting across the lava beds by dropping into the shadowy pleasantness of a convenient lava tube (formed by molten lava cooling faster on the surface while a hot river of lava continued to flow underneath, thus leaving a cave). You may see antelope here, and during summer a large colony of Mexican free-tailed bats migrates between some of the caves.. Bring several flashlights and protective clothing to explore the miles of lava tubes, but stay out of the bat caves. No groundwater exists in the entire area, so pack plenty.