An American Indian people of Yucatán and Central America who still maintain aspects of their ancient culture, which developed over an extensive area and reached its peak in the 4th–8th centuries, a period distinguished by a spectacular flowering of art and learning. Remains include stone temples built on pyramids and ornamented with sculptures. Among the most striking of the Maya achievements are a system of pictorial writing and a calendar system, more accurate than the Julian, that was still in use at the time of the Spanish conquest in the 16th century. The unexplained collapse of the early Mayan civilization with a population of as many as 16 million took place c.900–1500 but at least four million descendants still speak the Mayan language.