Mesoamerican tribe originating from the Yucatan peninsula around 2600 BC.
Most probably of the first people of America to developed astronomy, calendrical systems and writing (in hieroglyphs).

The Mayas had a very strong religion and they built all their important cities around big pyramid shaped temples - the biggest ones probably Chichen Itza and Tikal - the latter estimated to have had around 60000 inhabitants in the first part of the first millenium.

The temples were used to make sacrifices to the gods (the sun) of blood (the best sacrifice was blood from the penis of the king). Human sacrifice was also common.

As the sun was so important for the Maya religion, the Mayas had an extremely precise calendar. Big observatories were built to track the movement of the sun (and planets and stars as well), leading to a calculation of the duration of the year that was only 19 minutes wrong (the Europeans didn't manage doing that until more than a thousand years later).

For some unknown reason, the Mayas always abandomned their cities and built new ones. It might have had something to do with their religion. This has luckily lead to the Spanish not discovering the cities (as the jungle grew around them and hid them) - which leads to having very well preserved cities even today.

Unlike practically all other indian tribes, the Mayas have maintained their culture and some of their religion until today (making them the oldest civilization on the planet - 4600 years old) - and about 6 million people living in Mexico, Guatemala, Belize, Honduras and El Salvador speak different dialects of the old Mayan language.