Al-Andalus had highly urbanized societies centered around important cities like Cordoba, which was one of the largest cities in the world during the 10th century with over 100,000 inhabitants. Muslim cities were laid out with fortified walls and an alcázar or citadel at the center for political and military purposes. The medina contained the main mosque and souk market at the city center, while artisans lived in outer arrabales neighborhoods. Cities featured baths that were an important part of Islamic culture and hygiene practices.