When touring Chichen Itza we saw a cenote, similar to this one. We learned that it was used a sacrificial site where small boys and infants were given to the gods for water and other reasons. Also, many jewels and other valuable items were sacrificed. At one point an English business man "bought" the area and drudged the bottom gathering all of the goods and jewelry. Sounds a bit sad and sacrilegious, doesn't it? Apparently, the items are now exhibited at a Cambridge musuem.