At the heart of the city lies the Medina of Tunis, built on a gentle hill sloping towards the Tunis Lake, a historical heart of the city and home to many monuments, including palaces, such as the Dar Ben Abdallah and Dar Hussein, the mausoleum of Tourbet el Bey or many mosques such as Zitouna Mosque. Inside the Medina lie the souks, a network of covered streets lined with shops and traders and artisans ordered by specialty. Clothing merchants, perfumers, fruit sellers, booksellers and wool merchants have goods at the souks, while fishmongers, blacksmiths and potters tend to be relegated to the periphery of the markets.