I first visited Teotihuacan way back in 1979 and recently returned in January of 2026. This awesome site thoroughly impressed me both times. One of the grandest of all the ancient Mesoamerican sites you can visit with its three major pyramids: Sun, Moon, and Citadel. The Citadel is particularly interesting because it was built over an earlier temple to Quetzalcoatl, which is been excavated and exposed, so you sort of get two in one. The "Avenue of the Dead" is the main axis connecting the major pyramids. If your time is very short, you can come to Entrance #2 and easily hit the Sun and Moon pyramids.

But the Citadel/Feathered Serpent is worth seeing.

When I visited in 1979, you could climb all the pyramids, including the Sun. In 2026, they had very recently re-opened the Moon to climbing (not to the tippy-top). On a sunny weekend in January, it was almost dangerously crowded going up the stairs, although the rest of the site wasn't too bad. I saw two guys exchange more words than necessary because one of them had inadvertently cut in front of the other for a nice photo spot on the top of the Moon Pyramid.

It is worth checking out some of the less famous parts besides the pyramids, including the Quetzalpapalotl complex near the Moon Pyramid and the Superimposed Buildings along the Avenue of the Dead where you can get some relief from the sun in actual shade.

I don't remember a lot of details from 1979, but the site seemed very mysterious and not well-understood back then. It seems we've learned a lot about it over the decades, such as the extent of Teotihuacan's trade with other cultures of Mesoamerica, a lot of which was illustrated in the Anthropology museum.

Biggest annoyance: the constant "jaguar calls" and "eagle whistles" from vendors and purchasers. I don't mind most souvenir sellers so much, but these noisemakers really detract from enjoying the site.

I almost forgot to mention: You can buy tickets for Teotihuacan and other major INAH sites (e.g. Anthropology Museum in CDMX) online. Do it! Why not save yourself the wait in line, even if it is a relatively short one? I bought our tickets online with my phone after arriving at Teotihuacan and seeing the 20 minute line.