Abstract The most convenient place to see the Craters of the Moon (COM) lava field is at Craters of the Moon National Monument, reached by U.S. 20-26 from either Arco or Carey, Idaho (Fig. 1). A 7-mi (11-km) loop road and several hiking trails provide accessto volcanic features within the Monument Fig. 2. The 20-mi long (32-km) Wilderness Trail is the longest of the trails and requires a permit for overnight trips; there is no potable water available along this trail. The east, south, and west edges of the COM lava field can be reached by four-wheel-drive vehicles on unimproved roads that are shown on U.S. Geological Survey 7½-minute quadrangle maps of the area. The geologie map of the Inferno Cone Quadrangle (Kuntz and others, 1986c) depicts the volcanic features that are most accessible to visitors to the monument. Please note that hammers may not be used and samples may not be taken in the monument.