You need to carry sufficient light and may have to crawl on your belly like a reptile through mud. There may also be climbs, walkways slippery with mud, and underground streams to wade through. Caving is not always comfortable. I have never been on a trip where anyone has gotten worse than a few bruises, but I do not want people to think that caving is free from hazards. On the other hand, caving does have its points.
Ghost stories take on a new dimension underground with the lights off.