Bosque de Agua

The Bosque de Agua, or Great Water Forest, is not a single park with a ticket booth but a band of forested mountains, about 250,000 hectares in all, that separates Mexico City from Toluca and Cuernavaca. It takes in the Chichinautzin, Zempoala, Ajusco and Las Cruces ranges of the Trans-Mexican Volcanic Belt and is shared by 37 municipalities and boroughs: 22 in the State of Mexico (Xalatlaco, Ocuilan, Tianguistenco, Ocoyoacac, Lerma and Huixquilucan among them), eight in Morelos and seven in the capital. Some 21 protected areas lie wholly or partly inside it, and around 80% of the land is communally owned.

The name was coined by researchers at UAM Xochimilco, backed by Greenpeace Mexico, to make a point about what the forest does. Its high ground is the headwaters of four basins, the Valley of Mexico, the Balsas, the Lerma and the Pánuco, and rain soaking into it recharges ten aquifers. Those supply at least 70% of the water used in Mexico City and practically all of Toluca's and Cuernavaca's. The idea is old: in Nahuatl the Ajusco was Axochco, "where the water blooms".

The upper slopes are dominated by sacred fir (oyamel), mountain pine and oak, with coyotes, bobcats, opossums, squirrels and snakes in the woods and finches, hummingbirds and swallows overhead; the Xochimilco wetlands, also part of the corridor, are home to the axolotl. The corridor is under pressure from urban sprawl, illegal logging, fires and new roads, and in January 2025 the federal environment ministry and its enforcement agency signed an agreement to protect it with the governments of Mexico City, the State of Mexico and Morelos.

Travellers get to know the Bosque de Agua through its doorways: the Lagunas de Zempoala between Huitzilac and Ocuilan, La Marquesa on the Toluca highway, and the Ajusco and Desierto de los Leones on the Mexico City side.