Lava in Oregon?

What’s the first thing that comes to mind when contemplating a visit to Oregon? Chances are lava tubes weren’t among the responses. As it turns out, Oregon is a great place to explore volcanic landscapes. The city of Bend, along with several others nearby, are part of the central hub for caving activities in the state. The vast majority of the 690 caves in Deschutes County are lava tubes! These tubes were created by flows from the eruption of nearby Newberry volcano.

Measuring about a mile, the Lava River Cave is the longest lava tube in Oregon. Located about 15 miles south of Bend, it’s part of the Newberry National Volcanic Monument. Lava tubes are created by lava from volcanic eruptions flowing through to feed the front of the lava flow. When the lava river finally subsides, an empty “tube” is left behind. This tube was created by pahoehoe basalt lava, which is particularly fluid. The main tube of the Lava River Cave is the longest known, uncollapsed lava tube in Oregon. It was first “discovered” in the late 1800s. The temperature in the cave is a cool 40°F year-round (leading wise, early settlers to use it to store venison).

Tube Features

As you enter the first chamber near the entrance, the floor is rough and rocky. There are many fallen rocks, since this area closer to the surface is where most freezing and thawing occurs. About 1000 feet in you get to aptly named Echo Hall. Throughout the walk, we noticed edges and ledges indicating the way the lava flowed through long ago, much like a river. There are signs of currents and eddies, jagged spots and smooth ones. These smooth spots were formed after the lava drained, and trapped gases remelted volcanic rock! There are some geologic formations similar to other caves, and some specifically volcanic. Hollow cylindrical “soda straws” were formed by escaping gases. Cone-shaped formations were created by remelted lava dripping down from the ceiling and walls. Lava stalactites were dubbed “lavacicles” in early writings about this cave. Toward the back of the tube, the ground becomes more and more sandy. The sand gets thicker and thicker until it completely blocks off passage. We made it as far as hands and knees would allow. The tube is just over a mile (2.2 miles round-trip).

Visit Lava River Cave

Lava River Cave is open May through September. There’s a small admission fee, and you can rent a lantern at the entrance gate (you’ll need it if you don’t have one of your own). Lava Lands Visitor Center is just about a mile away. There you can learn more about the history and geology that make this area so fascinating. There are some good maps, interpretive exhibits and rangers on hand to explain it all! There are some good hikes nearby, and the woods are beautiful. We saw lots of deer on our walks outside the tunnel around the area. The Trail of the Molten Land, Whispering Pines Trail and Sun-Lava Trail can all be accessed from the Visitor’s Center.