 Important archaeological finds of the remains of structures built by the indigenous peoples of Mexico have been made in the country.The Mesoamerican civilizations that arose there developed a sophisticated architecture that evolved from simplistic to complex forms; in the north it was manifested in buildings of adobe and stone, the multi-storied housing as seen in Paquimé, and the cave dwellings of the Sierra Madre Occidental.Monte Albán was long the seat of the dominant political power in the Central Valleys of Oaxaca, from the decline of San José Mogote until the demise of the city, which occurred around the 9th century.