Available from May to October Only. The cave is closed during
the winter.
A dirt parking lot is available adjacent to the Subway Cave.
There is a very short trail from the parking lot to the cave that
includes short sections of stairs to get in and out of the lava
tube. The lava tube itself is just about 1/3 mile. Two reliable
light sources are highly recommended. The temperature remains
relatively cool throughout the year and will be quite refreshing in
the hot summer. Donations are accepted at a drop box.
This lava tube one of many formed approximately 20,000
–30,000 years ago in the Hat Creek Lava Flow. (The Subway
Cave information and the Splatter Cone informational panels and
pamphlets disagree on the exact age of the flow) The source of this
flow is about 16 miles to the south at the Splatter Cone EarthCache
(link). The surface of portions of the lava flow cooled and
hardened forming an insulating cover. Molten lava continued to flow
under it. When the eruption ended, the lava continued out the end
of the tube leaving an empty void under the solid surface.
Typically, lava tubes are sealed on both ends with rock, but in
some places the surface has collapsed creating entrances.
The same insulation that kept the lava hot as it flowed through
the tube keeps the air inside cool. The temperature fluctuates only
slightly throughout the year.
Inside the lava tube are a number of features that are frozen
into the solidified rock. There are ripples along some portions of
the cave floor from the flowing lava. There are a series of
information panels marked by reflective tape set in the cave. They
explain some of the individual features in the cave and how they
formed.
.
Send me a note with :
- The text "GC25BAM Subway Cave" on the first line
- The number of people in your group (put in the log as well),
along with the names of the geocachers you are sending your e-mail
for.
- How many different flows went through this tube? What evidence
is there for that number? (see Wind Tunnel panel)
- What are the sparkles in Lucifer’s Cul-de-Sac.
- Answer the question on the Lavacicle Lane panel.
The following sources were used to generate this
cache:
- US Forest Service Information
Panels
- Subway Cave, Self-guided Trail. Lassen National
Forest, Hat Creek Ranger District
- Splattercone Self-guided Trail. . Lassen
National Forest, Hat Creek Ranger District