The Mayan Empire was a Mesoamerican civilization that thrived from around 2000 BCE to the arrival of the Spanish in the 16th century. It was known for its advanced knowledge in mathematics, astronomy, and writing, using a complex system of hieroglyphs. The empire was made up of city-states, each with its own ruler, and was located in present-day Mexico, Guatemala, Belize, and parts of Honduras and El Salvador. The Mayans built impressive structures, including pyramids and temples, often for religious purposes. They developed a sophisticated calendar system and were skilled in agriculture, growing crops like maize, beans, and squash. The decline of the Mayan civilization is attributed to various factors, including environmental changes, warfare, and social unrest.