The big city square you've seen on TV, in full vibrant color. And there are dozens of ways to take off from there. Below are just some of the most important
Grandiose as it is, it's also free to come in. The murals by Diego Rivera are the biggest draw, but for architecture and history alone, it's worth spending some time.
The oldest and biggest cathedral in Latin America, this one is worth a good hour or two before lunch.
The Gran Hotel Terrace has an excellent terrace buffet with views from about five stories up. Highly competitive, it's in reality one of the best lunch buffets on the market.
While Anthropology can give you a pretty good perspective on the entire country, the Templo museum and site are focused just on what was here.