There have been many stories of "dark, shadowy figures" observed within the cave.
Update 11/5/22: Nicky Paton, the Royston Cave Manager replied to my query about any recent phenomena: "I am in the cave frequently and have not experienced anything myself. However, a few years ago, a lady seemingly appeared to give birth to a spirit and a couple of people have experienced feelings of warmth, but otherwise it's pretty normal."
Link: Royston Crow
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