The Old City of Baku, also known as the Walled City of Baku, refers to the ancient Baku settlement. Most of the walls and towers, strengthened after the Russian conquest in 1806, survived. This section is picturesque, with its maze of narrow alleys and ancient buildings: the cobbled streets past the Palace of the Shirvanshahs, two caravansaries, the baths and the Juma Mosque (which used to house the Azerbaijan National Carpet and Arts Museum but is now a mosque again). The old town core also has dozens of small mosques, often without any particular sign to distinguish them as such.