«to the bat cave» What do you do with the hollowed limestone caves from mining? Seal the ceilings and pour some concrete floors. They also run ducts to the surface for fresh air and add plumbing & electricity. What a tenant can get is some of the coolest office/work/warehouse space available(literal & «batman cool») Caves will naturally want to stay about 55 degrees so if you want it cool… rent this space. Humidity is the main concern so dehumidifiers are needed for most uses. Still, to say I worked in a cave is cool(even just sealing the floor). The high ceilings are painted white with sealer and the space between the support columns are scary big so the place never feels cramped. Check out the website