Who'd ah thunk? An ice cave in the land of triple digits. Invariably, each day by early afternoon, the temperature would rise from double to triple digits. The two hottest days experienced were back to back 114 degrees. Souvenir t shirts say "But it is a dry heat".
How does anything stay frozen out here? It began with 2000 degree lava, erupting from nearby Bandera Volcano about 10,000 years ago. The lava broke through this side of the cone and flowed for 23 miles, the longest lava flow in the US. The exterior of the lava begins to solidify while the interior continues to flow creating a tube. Over time the tube collapses as in the photo above. Where the tube remains intact, you have a lava tube cave. Lava is an incredible insulator and being mostly in the ground, conditions are good for maintaining a cool environment. Rainwater and groundwater have collected in the bottom of the lava tube. The original cause of ice formation is not known. The oldest ice is 3400 years old. The cave never gets above 31 degrees. It was used to keep beer cold at the local saloon. Now it is 20 feet thick and some is green with algae.
There is a point on these stairs where you very quickly transition from 100 to 50 degrees and then gradually to 31 if you were to reach ice level.
Looking back up through the collapsed tube
Icicles
The volcano cone. Or what is left of it.
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