They probably capture aliens and do bizarre things with their innards. And I can see them experimenting with hyper drives and new flying techniques.
Maybe they keep all the dinosaurs there that Bilbo reckons live side by side with man. It's like a big Jurassic Park underground and all these government officials are having a whale of a time hanging with Brontosaurus types and even psycho little raptors.
A big mystery that place. I wouldn't mind breaking in one day.
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