Teotihuacán guards secrets we have yet to unravel. The origins of Teotihuacán are uncertain, although it is thought some of the inhabitants arrived from the Valley of Mexico to the south, refugees from an eruption of the Xitle volcano, which caused major devastation and forced the survivors in the region to seek a new place to settle. Construction of the city probably started in the first two centuries BC, and the civilization reached its high point between 350 and 650 AD.
Scholars in archaeology agree that this is Mexico's - and perhaps the one of the world's - most important archaeological sites. It was the largest city in the Americas, and during its heyday around 500 AD, its population was greater than that of Rome at the same time.
One of the greatest mysteries of Teotihuacán is that no one knows where the huge population that lived here eventually ended up. It is as if they vanished without a trace.
This was also a place where human sacrifices were made, often in correlation with astronomical events. When the site was excavated, many tombs were found, some with the remains of what were believed to be people sacrificed to the gods.
Many people today believe that Teotihuacán is a place of great energy, and it is quite common to witness people meditating at the top of main pyramids (The Pyramid of the Sun and The Pyramid of the Moon).
This is truly a wonderful place to visit and is a "must do" if you happen to be in Mexico City. My best advice is to get there early before the tourist coaches arrive plus bring a hat and plenty of suncream!