Monte Alban
The second-largest ceremonial site in Central America and the capital of the Zapotec civilization originally stood at Monte Alban. It was formed by an amazing effort that included excavating a flat area out of a mountain rising to an elevation of nearly 1,600 feet above the valley below it. The location is still spectacular today. A number of civilizations, including the Olmecs, Zapotecs, and Mixtecs, inhabited Monte Alban for around 1,500 years, and at its peak, there were about 25,000 people living there.
A lot of people visit the place, especially on weekends. Monte Alban is extremely large, therefore it's wise to wear comfortable footwear. There isn't much shade, so if it's hot outside bring water and a hat. Great views can be had from Monte Alban, especially on a clear day.
Though there isn't much signage in English, there is a fine museum at the site's entrance that contains artifacts from the Monte Alban excavations. There are guides available; look for them at the entryway. Check their credentials because some are legitimate while others are not.
Location: Oaxaca, Mexico