There's a unique house for sale in Festus, Missouri. The eBay listing is here. The listing ends on March 11 or so (sooner if they get a good offer). If you go look, the photos in the middle of the listing may not show up - but there's more near the end.
The house is built into a cave. (Well, they call it a cave. Actually it's an old mine.) 17,000 square feet, spread over three chambers. The living area is in the front chamber. The second chamber is 40'x40', and makes a good party/game area. The third, or back chamber, is huge, and contains a stage where, back in the '70s and '80s or something, some well-known music groups performed. In the photos, the green-tinted tunnel-looking one is that third chamber. They really should have included a person in that photo for scale - the ceiling is over 20' high!
$300,000 can get you a very unique geothermal house.
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