In Mexico, the sacred ground of one religion often becomes the sacred ground of its successor. Cortés and his Spanish missionaries converted the Aztecs, tore down their temples, and used much of the stone to construct a church on this spot. The church they built was pulled down in 1628 while the present Metropolitan Cathedral was under construction. The building today has 5 naves and 14 chapels. As you wander past the small chapels, you may hear guides describing some of the cathedral's outstanding features: the tomb of Agustín Iturbide, placed here in 1838; a painting attributed to the Spanish artist Bartolomé Esteban Murillo; and the fact that the stone holy-water fonts ring like metal when tapped with a coin. Like many huge churches, it has catacombs underneath. The much older-looking church next to the cathedral is the chapel known as the Sagrario, another tour de force of Mexican baroque architecture built in the mid-1700s.

As you walk around the outside of the cathedral, you will notice a reminder of medieval trade life. The west side is the gathering place of carpenters, plasterers, plumbers, painters, and electricians who have no shops. Craftspeople display the tools of their trades, sometimes along with pictures of their work.