is the ruin of an ancient megopolis perched on a low mountain overlooking the entire Oaxaca valley. It's about 15 minutes by van from downtown. I've seen a fair number of ruins; European castles, Anasazi cliff dwellings, abandoned General Motors plants, etc... but this is bigger. Monte Albán was one of the biggest cities around for over a thousand years, with a population of tens of thousands of people. Then it was simply abandoned.
Here's what it looks like today (if you were 2,000 feet tall):
This view is pretty much what you see looking 360 degrees around the mountain - the populous Oaxaca valley. I'm sure the city commanded quite a presence to all the people living in the valley, but it must have been tough to get water.
This is the middle of the dry season, so all the grass is brown. When it rains the scene turns green.
One of the ball courts, for the Zapotec equivalent of fútbol:
Here's what the city must have looked like before excavation:
The experience is what I imagine it would be like to walk through a post-apocalyptic Manhattan, only with little placards explaining the purpose of each building.