Pluto's Cave

Pluto Caves

Useful Information

Location: North of Weed, near Mt. Shasta.
I5 exit 747 or 748 Weed, Highway 5 into town, turn off onto Highway 97, 20km north, turn left onto A12, 5km to a telephone pole marked with Pluto's Cave in silver letters, turn left onto the dirt road to the end (parking area). Path through the blocked off road to a graded road, turn right, at the street sign pole turn right into the rocks. Foot path to the cave entrance is well trodden.
(41°34'5.39"N, 122°16'58.25"W)
Open: no restrictions [2007]
Fee: free [2007]
Classification: ExplainLava Tube
Light: bring torch
Guided tours:  
Bibliography: John Muir (1888): Steep Trails
As far as we know this information was accurate when it was published (see years in brackets), but may have changed since then.
Please check rates and details directly with the companies in question if you need more recent info.


1863 discovered and named by Nelson Cash.
1888 John Muir describes his discoveries in the cave in the book Steep Trails.
1917 graffities by a Boy Scout troop.


Pluto's Cave is a 190,000 year old lava tube, which is pretty old for a lava tube. Normally they collapse rather soon, as the ceiling is only a few meters thick. However, collapse is a result of erosion, and this is a semi arid (dessert like) climate where erosion by water is restricted. Probably this is the explanation why this cave remaind about ten times the average age of lava tubes.

Pluto's Cave is a popular spelunking destination, definitely well developed by heavy use, it is rather simple to find ones way, as there are lots of trails created by lots of visitors. Nevertheless it is a wild cave, so bring at least two lights per person, sturdy shoes, warm clothes, helmet it you have and turn your mind on. We also highly recommend to tell someone the planned return time, so that he may call the rescue if necessary.

The cave was named after after the Roman God of the underworld by Nelson Cash, who discovered it 1863 while looking for stray cattle. However, this was definitely not the first discovery. Many evidences were found for its use by indigenous people long before Europeans arrived.