I’ve always been fascinated by the industry that occurred out in the countryside back in the day. The harvesting of guano, for the manufacturing of gunpowder, logically took place in caverns, and many subterranean spaces with active bat populations were located far from urban centers. Fisher Cave, in Meramec State Park, is one such site. I really enjoyed the heavy gate the Fishers originally used to closed the mouth of the cave. It failed to allow bats to fly through safely, so the State has replaced it with a fence that allows the safe and easy passage of bats back and forth through the cave entrance.