The Incas were an ancient South American civilization that flourished in the Andes Mountains from the 12th to 16th centuries. They were known as empire builders, having created a vast empire that extended from modern-day Ecuador to Chile. The Incas were renowned for their architectural achievements, including the construction of Machu Picchu and the terraced agricultural systems of the Sacred Valley. They also developed a complex system of government, with a strong emphasis on religious and social hierarchy. The Incas are remembered today as one of the most powerful and influential empires of the pre-Columbian Americas.