Pluto's Cave is a lava tube north of Mt. Shasta, California, about 1/2-3/4 miles in length. It is 190,000 years in age & was discovered in 1863, however prehistoric use of the cave is evident. John Muir visited the cave sometime during 1874-1875 & in the early 20th century it was used by the Improved Order of Red Men (as indicated by their graffiti). Near the south end, this lava bridge forms b/w two collapsed portions of the tube, which now serve as the main entrances of the cave. This was taken underneath the bridge. Like other caves in the area, graffiti & vandalism has taken their toll at this locality. The surrounding area has homes that are packed w/ marijuana farms (now that it's legal here).
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