Located within the Cascade Range in northeast California, Lava Beds National Monument preserves over 72 square miles (186 square km) of cinder cones, lava flows, and the largest collection of lava tube caves to be found in North America. These remarkable features have all emerged over the last half million years from the Medicine Lake shield volcano.
Although not as visually stunning as big composite cones like Mount Shasta and Mount Hood, the Medicine Lake volcano is actually much larger in volume. Reaching 7,900 feet (2,408 m) above sea level, this cone is a massive 150 miles (241 km) around at its base. It covers over 700 square miles (1125 square km) in area and has over 200 surface vents.
The volcanic rocks of three massive lava flows dominate the landscape of this park. The Schonchin Flow at the center of the park formed from a large release of lava from the Schonchin Butte cinder cone around 62,000 years ago. The Devils Homestead Flow in the northwest corner emerged around 10,500 years ago. Only about 1,100 years ago the Callahan Flow to the southwest belched from Cinder Butte just outside the park.
Although the black, nearly lifeless expanses of volcanic rock are certainly fascinating, it’s the approximately 700 lava tube caves that make this place a wonder to explore. Unlike most parks with caves, exploration of these subterranean wonders is done on your own without guides. Rangers at the visitor center will be happy to provide information and sell or loan flashlights or hardhats, but they leave you to yourself to see what these caves have to offer.
Many lava tube caves are found within a short distance of the visitor center. My wife and I made our first stop at Garden Bridges a short walk away. The “garden” part of the name comes from the relatively lush foliage that makes a home here in the cool shade and moisture.
The “bridges” part of the name comes from the fact that most of the ceiling has collapsed on this cave, leaving just a few “bridges” intact. Everywhere else skylights let in the sun, making this a relatively accessible spot for even claustrophobics to visit.
At the nearby Hopkins Chocolate cave, lava that hardened while still dripping adorns the cavern walls. The lavacicles may have reminded someone named Hopkins of melted chocolate.
These lava tube caves formed when rivers of lava that emerged from a vent began to cool and harden. The outermost surface hardened first, creating a tube of rock where still-liquid lava continued to flow. Eventually the lava ran out, leaving a hollow tube of hardened lava rock.
While this park hosts more caves that one could hope to visit on a single trip, we did try to see several with different features. Sentinel cave provided a long, narrow, dark passageway lit only by our flashlights.
Skull Cave was the largest one we visited. This is one of several “ice caves” in the park, so-named because their structures trap cold winter air within, making them quite chilly at their greatest depths even in summer. Many even have frozen ground water within them.
Back on the surface it was also interesting to see how life had re-established itself on the relatively young volcanic surfaces. Although many organisms likely perished when this lava spewed forth, it didn’t take long (in geologic terms) for life to re-assert itself.
The 10,500-year-old Devils Homestead Flow, while still largely barren, was slowly being taken over by plant life. Trees and various wildflowers were again getting a foothold, bringing color to the otherwise dark landscape.
Even in the middle of summer Indian paintbrush and other flowers were relatively common.
Although it may not look like much at first glance, Lava Beds National Monument holds some hidden beauty and is a great place to explore. It’s especially interesting if you’re into volcanism or primary succession in ecology. While a bit out of the way, if you’re in the area it’s worth spending at least a day here to take in some truly unique features.