Now we're looking at a couple of cenotes ("suh - no - tays"), which are small freshwater pools, usually spring-fed, that dot all of the Yucatan and Chiapas. Most (?) are the calderas of (presumably) extinct volcanoes. They are often see in conjunction with ruins, as they served an excellent water source, particularly in northern Yucatan, where it didn't rain nearly enough. In fact, Chaac (the Mayan rain god) is the most popular visage on all the best ruins. Although you're not seeing this (hey, gotta leave something for you to discover), minerals often color the waters, and the results can be remarkable. Lagos de Montebellos is a national park on the southern border, which has dozens of cenotes, ranging across the spectrum from red and green to the deep deep blue you see on the right.