Wildlife and greenery aren’t Mexico City’s calling cards.
But while the world’s fifth-largest metropolis is home to more than 21 million people, it’s also grounds for nearly 4,000 species of flora and fauna, and some 15 percent of its total area consists of national parks and other protected areas.
This stems from the city’s lush past. The sprawling conurbation started out as the Aztec capital Tenochtitlan, built on a swampy island in Lake Texcoco, one of five interconnected lakes circled by mountains and volcanoes.
Map of Valley of Mexico lake system in 1519. Madman2001, Wikimedia Commons
During the 15th century, the Aztecs built a sophisticated network of canals, levees and dikes to protect Tenochtitlan from the surrounding waters, as well as aqueducts to carry fresh water from springs located on the mainland. A ring of