Now, more than 20 million people live and work in this hectic, expanding mass of concrete.
The Mexican capital is host to an array of unenviable problems.
The gap between rich and poor is among the biggest in the world. The violent crime rate is steadily climbing.
More than four million cars clog the badly-planned and poorly-built streets.
Its toxic air causes breathing and skin disorders.
But, worse than any of this, it is sinking.
Like the world revolving, there is an imperceptible, but inexorable movement under way.