Largest Catholic cathedral in the Western Hemisphere, the Catedral Metropolitano is the focal point of the Zocalo, the square that marks the spiritual and political center of Mexico. The Spanish built the Zocalo right on top of the center of the Aztecs' capital city, Tenochtitlan, and utility crews working a few blocks off the Zocalo in the mid-80s unearthed significant Aztec remains, including a pyramid and temple complex. If you see a major political rally in Mexico City or the President of Mexico addressing a huge crowd outdoors, it's probably taken at the Zocalo.
This photo and two other photos my dad took in Mexico City were published in the French-language book Andre Pieyre de Mandiargues Pages Mexicaines, about a visit the writer made to Mexico in 1958. Photo by Walter Reed