Standing at La Plaza de Las Tres Culturas—an evolutionary intersection where Aztec ruins sit alongside a 17th-century church and 21st-century modernity—what you’ll first notice is that the church and the plaza are leaning. And that is because Mexico City is sinking. Yup, the entire city, in fact, is one big swamp, built in this location because here was spotted an eagle with a serpent in its talons, perched on a cactus—a prophetic sign for the Aztecs to build a city after wandering nomadically for several centuries.
For modern-day Mexico, that means that all over the city, there are leaning, sinking buildings as well as ruins that are retreating into the earth.
Aztec ruins in the foreground with La Basilica (the old one) leaning in background
By Deror_avi - Own work, CC BY-SA 3.0
La Basilica de Guadalupe, a modern structure (hideously out of architectural sync with the adjacent churches) that holds 10,000 parishioners, faces a plaza where you can also see the old Basilica (sinking), La Colegiata (sinking), and high on the hill behind, El Templo de Cerrito.
The story behind La Virgen de Guadalupe, which has produced a kind of cult following in Mexico, as well as becoming central to Catholicism in this part of the world, goes something like this:
In 1531 an Indian named Juan Diego was walking over the hill on his way home from church (the Indians walked for miles to attend services in the city) when the Virgin Mary appeared to him. Over a short period of time, she appeared to him several more times, each time telling him to send a message to the bishop to build a church on a nearby spot.
When the Indian approached the bishop, he wouldn't believe that the message actually came from the Virgin) and he asked for proof. When the Virgin appeared to Juan Diego again, he told her that no one believed him because he was an Indian, and they wanted proof. She gave him a bundle of red roses and told him to fold them in his jacket, take them back to the bishop, not showing anyone until he got there.
When he returned to the bishop he opened his jacket and the roses fell out. Imprinted on his frock was a perfect image of the Virgin. The bishop believed, and had the church built (the old Basilica).
The faithful make the pilgrimage to La Basilica de Guadalupe
By Karolja - Own work, CC BY-SA 4.0
The entire square is considered a holy place, a mecca for millions of people who make the pilgrimage to visit the site. Even poor people come from the outer regions of Mexico and camp out in tents on the plaza for several days. On the periphery are hundreds of vendors selling rosaries and images of the Virgin. The most pious crawl on their knees across the plaza, approaching the Basilica in prayer position.
While church services are going on, visitors can enter a passage behind the church altar and shuffle by the huge 24K gold framed frock of the young Indian and you can clearly see the colorful image of the Virgin peacefully looking down. The guides joke that instead of being called "catolicos," Mexicans are often called "Guadalupanos"—for such fervor around La Virgen de Guadalupe.
Regardless of your religious leanings, it’s well worth seeing the churches and holy spots of Mexico City—before they sink into the earth.