Our resort (Mopan River Resort) organized the tour for us. The original founder of the cave, Will, gave us a tour.
He began by leading us through a hike through the jungle. It wasn't too difficult of a hike, but there was a man with us with bad knees who slipped frequently, so I wouldn't recommend the trip for anyone who isn't fit to really hike.
At the cave, we all put on our headlamps, and we were led inside. Inside, there are bats and spiders, but, more importantly, ancient Mayan pottery. The caves were were the Mayans held their funeral rites, so we learned about their ceremonies and even were shown one of their blood-letting alters.
My husband loved the hike and learning about the vegetation and the actual caving. I loved the pottery and the history behind the cave. The trip really offered something for everyone.
The pottery cave was found by a teenager years ago and the tours are given by the discoverer. A moderate hike up a hill leads you to the cave where you descend slowly (you are not lowered by rope, you climb down) and view stalactites and Mayan pottery.
If you are staying at Mopan this is one of their regular trips
The Mopan is an easy kayaking trip. Small dips make the trip interesting and the slow pace makes nature and people watching easy. We saw an iguana sunning itself on the bank and residents washing their clothes and their children. Watch out for trees over hanging the river, we had a nasty run in with one.
I doubt if this is a custom but it did catch me totally by surprise. There were a lot of chickens running around and a couple of kids ran out of the house, chase down a chicken, and took it back to their house.