Cayo Scoop! The Ecology of Cayo Culture

ATM gets a great review.  The author really describes the journey and the magic of the cave, which is number 1 on National Geographic's Sacred Caves list.  

"When we began planning our trip to Belize last winter, Actun Tunichil Muknal (or ATM as everyone called it) was a name that appeared often in travel guides and in conversations with people who had been to that country before.  'If you can only do one thing while you're in Belize, this is the one you can't miss.'  At first I was intrigued by the challenge.  A cave.  A long hike just to get to the mouth.  A longer hike to the end where a centuries old intact skeleton lay.  A guide required and only a limited number of people allowed in a group."

ATM mentioned in an interesting way.

"Actun Tunichil Muknal, or ATM, is one of the most well known ceremonial caves in the entire world. It has been voted by National Geographic to be the #1 sacred cave to visit, and is a big draw for tourism in Western Belize. Caves were considered to be very spiritual places to the ancient Maya. As an entrance to the underworld, the Mayans would often hold ceremony and prepare offerings to their Gods, and occasionally ritual sacrifice. Deep within the ATM cave is a cavernous series of dry chambers that hold the remains of hundreds of ceramic bowls, pots, and shards which have essentially calcified over the years by the natural drippings of limestone. Rather than remove the items, the government of Belize decided to leave them in their positions, and to make the cave, and its contents, the museum. Guides must also be certified as museum curators; and clean socks are packed into the cave to be worn when you reach the inner chambers."