The Maya civilization was a Mesoamerican civilization developed by the Maya peoples, and noted for its hieroglyphic script—the only known fully developed writing system of the pre-Columbian Americas—as well as for its art, architecture, mathematics, calendar, and astronomical system. The Maya civilization developed in an area that encompasses southeastern Mexico, all of Guatemala and Belize, and the western portions of Honduras and El Salvador. This region consists of the northern lowlands encompassing the Yucatán Peninsula, and the highlands of the Sierra Madre, running from the Mexican state of Chiapas, across southern Guatemala and onwards into El Salvador, and the southern lowlands of the Pacific littoral plain. The Archaic period, prior to 2000 BC, saw the first developments in agriculture and the earliest villages. The first Maya cities developed around 750 BC, and by 500 BC these cities possessed monumental architecture, including large temples with elaborate stucco façades. Hieroglyphic writing was being used in the Maya region by the 3rd century BC. In the Late Preclassic a number of large cities developed in the Petén Basin, The Maya developed a highly complex series of interlocking ritual calendars, and employed mathematics that included one of the earliest instances of the explicit zero in the world. As a part of their religion, the Maya practised human sacrifice.