Monte Albán (mōnˈtā älbänˈ) [key], ancient city, c.7 mi (11.3 km) from Oaxaca, SW Mexico, capital of the Zapotec. Monte Albán was built on an artificially leveled, rocky promontory above the Valley of Oaxaca. Located around an enormous plaza about 1,000 ft (300 m) long and 650 ft (198 m) wide are long, low buildings set off by sunken courts and stairways. The tombs, particularly Tomb 7, have yielded great archaeological treasure—jewelry of gold, copper, jade, rock crystal, obsidian, and turquoise mosaic and bone and wood carving showing elaborate religious symbolism. Excavation was begun (1931) by the Mexican archaeologist Alfonso Caso. The Zapotec apparently had an advanced culture here c.200 B.C. and already were using the bar and dot system of numerals used by the Maya. The final epoch (c.1300–1521), terminated by the Spanish Conquest, covers the ascendancy of the Mixtec, when the Zapotec were driven from Monte Albán and Mitla. Tomb 7 belongs to the final period. Cultural links with the Olmec and the Toltec have been found.