Yucatan

The Yucatan peninsula is bordered on the north and west by the Gulf of Mexico and on the east by the Caribbean Sea. The peninsula is a large shelf of land that projects eastward out of the main body of Central America. The entire region is hot, with northern areas drier than the southern areas. Turkeys, jaguars, coatimundis, and tapirs are found among the palms, mangroves, and wide variety of broadleaf vegetation found in the tropical rainforests. The thick canopy of the tropical forests is broken by the jutting of man-made stone mountains - the ruins of the ancient Maya civilization. One of the most remarkable sites is the city of Chichen Itza, mysteriously abandoned by the Maya around 1400 CE after 1,000 years of settlement and about 100 years before their first encounters with the Spanish. During the spring and fall equinox, at the great pyramid in the middle of Chichen Itza, a shadow appears on the tall steps, appearing like a serpent ascending the stairs. Little is known about why the Maya suddenly abandoned this city.

From the game's History encyclopedia, AoE3: DE 100.19.18309.