Bonn archaeologists find huge artificial lake with a ceramic-lined floorSince 2009, researchers from Bonn and Mexico have been systematically uncovering and mapping the old walls of Uxul, a Mayan city. "In the process, we also came across two, about 100 m square water reservoirs," explained Iken Paap, who directs the project with Professor Dr. Nikolai Grube and the Mexican archaeologist Antonio Benavides Castillo. Such monster pools, which are also known from other Mayan cities, are called "aguadas." Similar to present-day water towers, they served to store drinking water. But the people of Uxul seem to have thought of a particularly...