People swim in the fresh, cool waters of the sacred blue cenote (sink hole) at the Ik Kil Eco-archeological Park (cq) near Piste, Yucatan, Mexico, on May 22, 2007. Tree roots hang about 80 feet to the water. Ik Kil is a popular cooling-off spot for tourists visiting nearby Chichen Itza.  (© 2007 Cindi Christie)