I was at Cholula a few years ago and was interested to learn that it, like Teotihuacan, was built aside a large ancient lake. There is no lake near the ruins of Cholula today. It is a heavily-populated part of the state of Puebla and the local water table has been dramatically drawn down over the years through stream diversion and pumping. Ditto Lake Texcoco, The modest floating gardens of Xochimilco on the extreme south of sprawling Mexico City are all that is left of what once was a very large lake. Actually, Texcoco was five adjoining lakes: Chalco, Xochimilco, Texcoco, Xaltocan, and Zumpango, with a combined surface area of about 1,400 square kilometers. That is more than 3 times the size of Utah Lake which has a surface area of about 380 square kilometers.
On June 29, 2019, I spent time with Mexican historian Diego Velazquez near his home in Lerma east of Toluca. I asked about Lake Lerma south of the city. He said anciently it was considerably larger, covering much of the Toluca Valley, with settlement sites around the shores. Its ancient name was "Chignahuapan" which means "place of nine lakes." There were also shallow lakes called Chimaliapan and Chicnahuapan. So, Mexico City, Toluca over the mountains to the west, and Cholula over the mountains to the east, were all once part of a land northward with large bodies of water.
Region in Central Mexico that Anciently had Many Large Lakes |
Relative surface areas:
Lake Texcoco, Mexico 1,400 square km
Lake Chapala, Jalisco 1,100 square km
Utah Lake, Utah (largest freshwater lake in the US west of the Mississippi) 380 square km
Lake Zacuapa, Michoacan 350 square km
Bear Lake, Idaho & Utah 280 square km
Lake Chignahuapan, Mexico 250 square km
Lake Catemaco, Veracruz 72 square km
This band of ancient lakes roughly corresponds to the area Mexican geographers call the "Cinturón Volcánico Transmexicano" or CVT. In English it is the Trans-Mexican Volcanic Belt formed by plate tectonics. The more than 20 volcanoes in this belt include Pico de Orizaba (5,636 meters), which is the highest volcanic peak in North America. Popocatépetl (5,393 meters) is the second highest peak in Mexico and Iztaccíhatl (5,230 meters) is the third highest in the country. Moisture-laden clouds rising up the slopes of the 20+ volcanoes in the Trans-Mexican Volcanic Belt result in the abundant rainfall that fed the ancient rivers and lakes in this fertile region. Many of these volcanoes are snow-capped during the winter months.