The Scuba News New Zealand

While people adept at holding their breath have been exploring the underwater world for a long time, scuba diving is relatively new. In a history of the National Association of Underwater Instructors (NAUI) written by Albert A. Tillman and Thomas T. Tillman, the authors say the first “aqua lung,” was not introduced until 1949. It was developed by Jacques-Yves Cousteau and Emile Gagnon.

When the Aztecs founded Tenochtitlán in 1325, they built it on a large island on Lake Texcoco. Its eventual 200,000-plus inhabitants relied on canals, levees, dikes, floating gardens, aqueducts and bridges for defence, transportation, flood control, drinking water and food. After the Spaniards conquered the city in 1521, they drained the lake and built Mexico City over it.