The volcanoes of Hawaii
have provided a venue for recreation and scientific discovery for nearly a
century. Prior to the establishment of Hawaii National Park
in 1916, the area was home to native Hawaiians for over 500 years. They
considered the volcanoes and surrounding land to be sacred. The park, renamed
Hawaii Volcanoes National Park in 1961, provides opportunities to see active
and historic lava flows, steam vents, various types of lava, and the rock
formations that result from volcanic activity. One of the park's features is a
dormant lava tube known as Thurston Lava Tube.
What Are Lava Tubes?
Lava tubes are the natural conduits through which lava flows -- or once flowed
-- underground. Most lava tubes form in molten pahoehoe
lava flows, with a zone of active flow in the middle of an area of solidifying
lava. (Pahoehoe is the smooth or wavy sort of lava,
as opposed to the rough and chunky aa
or a'a lava.) Picture a stream of flowing lava. Now picture that the surface of this molten-hot stream, upon
exposure to the cool air above, will start to solidify from the top down.
This "crust" insulates the underlying lava, allowing it to remain fluid and
continue to flow within the hardened crust. Once the eruptive activity of the
volcano causing the flow diminishes or stops, the supply of new, flowing lava
slows and eventually stops. The lava flows on through like water from a
shut-off hose, decreasing in flow and height within the tube. The flow
eventually stops and leaves behind a hollow "tube" or tunnel.
Well-known and accessible lava tubes in the United States include Ape Cave at Mount
St. Helens in Washington State; Valentine Cave in Lava Beds National Monument,
California; and Thurston Lava Tube in Volcanoes National Park in Hawaii.
Thurston Lava Tube
Thurston Lava Tube is named for its discoverer, Lorrin
A. Thurston. Grandson of a Protestant missionary, Thurston was born in Hawaii in 1858 and
became a lawyer, politician, and newspaper publisher there. He was involved in
the overthrow of the Hawaiian monarchy and the advancement of American
interests in the islands as well as the establishment of what became the
national park. Thurston is credited with discovering the lava tube in 1913.
The interior ceiling of the tube was once covered with stalactites, but
those have all but disappeared over the years at the hands of misguided
souvenir seekers. Today, a 1/3-mile section of the lava tube is lighted and
quite easily traversed by anyone without mobility impairment in about 20
minutes' time. (There is more of the lava tube that can be explored if you have
a flashlight or headlamp.) While the lighted segment is a bit of a sterilized
lava tube experience, it definitely gives one the sense of being inside a lava
cave, just one of many capillaries within this volcanic area leading to the
Most visitors to Volcanoes National Park
will take at least part of the Crater Rim Drive Tour, which includes a section
of a caldera rim as well as both rain forest and desert ecoscapes.
This driving tour affords opportunities to pull off the road and sample
viewpoints and short hikes including the stroll through the lava tube. The
entire Crater Rim Drive
is paved and easily driven in a standard 2WD vehicle. Note that sometimes (as
when I visited in spring of 2011), portions of the
drive may be closed due to volcanic activity and/or air quality issues.
If you begin your drive at the main visitor center and proceed in a
clockwise direction, points of interest are sequentially numbered. Stop #10 is
the Pu'u Pua'i Overlook,
and the Thurston Lava Tube is Stop #11, 1.3 miles thereafter. You can also
reach the lava tube via the Kilauea Iki hiking trail,
one of the park's most popular hikes and one I highly recommend. If you hike
the 4-mile trail counterclockwise (beginning with the rain forest and ending
with the caldera floor), you reach the very short spur trail to the Thurston
Lava Tube just after you climb out of the caldera and before the last flat
stroll to the Kilauea Iki Trailhead.
Sally O'Neal has written about her trailside adventures for sportsmansguide.com since 2000. She visited Thurston Lava Tube in spring of 2011. For more
information on Hawaii
Park, visit the official website at http://www.nps.gov/havo/.