Here are some of the pictures that Simeon Leland took of Mexico in 1950:
Based on the clothing that people are wearing, his photos were probably taken in Oaxaca or Chiapas. This guy, judging by his pants, has probably been to Los Angeles or thereabouts.
The Zocalo, Mexico’s main square:
Below you can see what the same space looks like in 2007. Fewer trees, no cars, more people, a metro stop that you can’t see. Another thing that you can’t see: the Templo Mayor of the Mexica / Aztecs, which was thought to be lost but in fact is right next to this cathedral. It wasn’t found until the late 1970s, so although you can’t see it in either photo, it wouldn’t have been there at all in 1950.
I enjoyed my experience at the Zocalo in July ’07. I can attest to the sky being blue, the air being quite breathable. I was also amazed by the history beneath the square. The Spanish literally covered the huge Aztec temple of Tenochtitlan, on top of which they built their own architectural symbols of religious and political power. The Zocalo represents a significant turning point in the history of Mexico, which I learned to appreciate during my visit to see Patrick, Nicole and Mexico City.