The ejido (Mexican system of communal land tenure) has been the indivisible unit of land ownership in Mexico ever since the approval of the 1917 Constitution. More than one-hundred million hectares of fertile ground were granted to groups of people under a very clear set of rules: the land would belong to the state, and by eliminating private ownership over it, conflict, division, and indiscriminate usufruct would be avoided. The use of the land would be decided upon by the beneficiary farmers of the ejido, provided that it may be for their own agricultural use; the land would not be sold nor divided; ejidos would not become “latifundiums” (large parcels of generally unused land) nor minifundios (smaller versions of latifundiums); it may not be given industrial use nor may be annexed to neighboring cities (which tend to grow horizontally). The people east of Lake Texcoco established themselves under this model of land ownership, thus consolidating themselves as communities dedicated to planting, farming, and raising livestock, remaining thus protected from being absorbed by Mexico City’s strong forces of urbanization, despite these communities would thrive next to neighborhoods on their eastern margin. [...]