Air pockets trapped under lava flow create Buffalo Caves at Craters of the Moon in Idaho, USA.
The continuation of the Broken Top Loop Trail, from Marker # 7, is guided by posts across the lava crust to the entrance for Buffalo Caves.
These under-surface lava tubes are accessible at Marker # 8.
The relatively inconspicuous main entrance to Buffalo Caves is near Big Cinder Butte which has a thriving aspen tree forest on the north facing side of the formidable and distinctive volcano.
Nearby are excellent examples of lava toes which form at the edge of the crust when hot lava oozes out from underneath.
A permit, available at the Interpretive Center, is required to enter any cave in Craters of the Moon National Monument. Everyone is screened by questionnaire to reduce the spread of White-nose Syndrome to protect bats. The permit must be left visible in the vehicle.
If the vehicle remains in the parking area after closing, someone will be looking for the occupants. Buffalo Caves are the only subterranean lava tubes we will be able to access today.
The next spur road on the 7 mile, one-way loop road is unfortunately closed for trail maintenance. At that location, there are better caves to explore. They are Dewdrop Cave, Boy Scout Cave, Beauty Cave and Indian Tunnel.
Backpacks are left at the entrance for the short scramble, with headlamps, into the lava tube.
Buffalo Caves are part of the lava tube system of the Broken Top flow. Crusts of cooling lava form over rivers of hot, flowing lava.
The lava river beneath the crust becomes insulated from cooling air allowing the hot lava to continue to flow. Eventually the molten lava drains away, evacuates the space and leaves an open lava tube or cave.
The height of the lava tube varies. There are several squeezes off to the sides and some of these can be explored with varying degrees of success.
Sharp rock is an issue. One section of the cave is taped off due to a ceiling collapse. It is unusual to explore a cave with a relatively flat floor.
Exit is achieved through a squeeze into a different location followed by a scramble into a large cavern at the other end of the Buffalo Cave structure.
This is simply too much fun!
Time is taken for much needed food and beverage outside and above Buffalo Caves prior to completing the Broken Top Loop Trail which is an outstanding educational and recreational experience within a broad range of terrain and features.
Back at the trail-head is the adjacent trail to Tree Molds.