The West Malpais Wilderness is a flat landscape of 18,000 year old volcanic lava flows. The southeastern portion of the wilderness is a grassland with expansive views. The western portion is a piñon-juniper woodland and the northern portion is characterized by ponderosa pine. The most distinctive landform within the West Malpais Wilderness is a 6,700-acre kīpuka (a Hawaiian term meaning island of fertile ground) in the north part of the wilderness called Hole-in-the-Wall. Hole-in-the-Wall is encircled by jagged basalt flows. The Wilderness is located within the El Malpais National Conservation Area.