We took our 5-year-old son, who is very interested in science, rocks/minerals, and geology. This was very exciting for him. We adults also enjoyed the tour. Our tour guides, Jenny, and Jamie (who was in training) did a great job. They made it fun and educational. The stalagtites and stalagmites were interesting and beautiful. We liked the fossil and mineral education. There are several stairs and semi-steep walkways, so if walking is an issue for you, that's something to consider. There are some areas in which the walls are briefly fairly close together; the majority of people probably would not have a problem fitting through, but if you happen to be larger, and/or are very nervous with small spaces, it could be slightly uncomfortable. If you're tall, you must duck in a few places, but you don't ever have to crouch too low. We saw just a few tiny bats. They stayed high above our heads, did not come near us or pay any attention to us, and only one of them was actually moving. Most of them were sleeping soundly. Walkways are sufficiently lit. We still had to keep a close eye on our young adventure-seeking son to ensure he did not wander off or step into any dark areas. He happened to be wearing light-up tennis shoes, which turned out to be helpful. I wished I had brought along a glow-in-the-dark stick for him, just for fun. You can take pictures, but they discourage too much use of flash; I think they said it was to avoid bothering the bats. In one room, they do shut off all the lights for a couple of minutes just to "achieve total darkness," but they do ask everybody in the group if it's ok first. In a separate room, they turn off the main lights and use a blacklight for a demonstration. The gift shop is very nice with lots of neat finds. We purchased the "prospector's package" for our son only; we didn't need to pay extra for the adults to have the experience too. He liked sifting through the sand, via pumped water and a screen/box, to find rocks (which he gets to keep). He also liked pressing a penny in the gift shop's entrance. A couple of "duh" items to remember: no cell phone reception, no bathrooms.Take a sweatshirt along, as it's 50 degrees down there, year-round. (In the winter, that's a heat wave for us Wisconsin-ites...but it's still a damp 50 degrees). Wear good walking shoes, which you don't mind getting just slightly dirty. Walkways are mostly paved with tiny pebbles, but are slightly wet from drops of water coming from cave ceilings.