The Oaxaca Valley is a geographic region located within the modern-day State of Oaxaca in southern Mexico. The valley, which is located within the Sierra Madre Mountains, is shaped like a distorted and almost upside-down “Y,” with each of its arms bearing specific names: the northwestern Etla arm, the central southern Valle Grande, and the Tlacolula arm to the east. The Oaxaca Valley was home to the Zapotec civilization, one of the earliest complex societies in Mesoamerica, and the later Mixtec culture. A number of important and well-known archaeological sites are found in the Oaxaca Valley, including Monte Alban, Mitla, San José Mogote and Yagul. Today, the capital of the state, Oaxaca City, is located in the central portion of the valley.