We did this in October 08. It is in Cozumel. However you need to take the 45 min boat ride to the main land and then a short bus ride to the location. You will snorkel in a water filled cave. It is fairly cool water but interesting. You will also swim in a Cenote that is outside. In one of the dry Cenote or caves you will witness a maya ceremony. It is done in the native Maya language. You will also get to ride some zip lines. In fact there are three, each one just a little higher than the other. The last part is to see some Mayian farming. We ran out of time and opted to forego this. The four activities are not always done in the same order. In fact the larger group divided into 4 groups and each did a different activity. Our group was only about 10 people. A really good size. The meal was good and I would recomend this excrusion. There is a word to the wise, it is a very long day and this may not be the best for those with young children. Also the 45 min ride to the mainland can be bumpy and if you are prone to getting seasick might not be a good choice either. Any other questions given the brief amount of info I have provided?