The Avenue of the Dead is roughly 40 meters wide and 4 km long. Further down the Avenue of the Dead, after a small river, is the area known as the Citadel, containing the ruined Temple of the Feathered Serpent Quetzalcoatl. This area was a large plaza surrounded by temples that formed the religious and political center of the city. The name "Citadel" was given to it by the Spanish, who believed it was a fort. Most of the common people lived in large apartment buildings spread across the city. Many of the buildings contained workshops where artisans produced pottery and other goods.