The medieval palace of the Shirvan Shahs is the highlight of the Old City and a must see for any tourist in Baku. The complex contains the main building of the palace, Divanhane, the burial-vaults, the shah's mosque with a minaret, Seyid Yahya Bakuvi's mausoleum, a portal in the east - Murad's gate, a reservoir and the remnants of the bath-house. - The main building of the complex was started in 1411 by Shirvanshah Sheykh Ibrahim I. The two-storey building of the palace numbers about 50 different dimensions and outlines of the constructions connected with 3 narrow winding staircases. The big lancet portal directly leads from the courtyard to the second floor, into a high octahedral lodging covered with a cupola. A small, also an octagonal vestibule, located behind it, connects it with the rest of the lodgings in the palace. - Divankhana is a small stone pavilion. It is situated inside a small courtyard surrounded by a gallery-arcade on three sides. The Divankhana pavilion consists of an octahedral hall covered with a stone cupola both inside and outside. The well-proportioned high portal of the main entrance is decorated with an ornament and Arabic inscription. The ornament pictures the interlacing fig and vine leaves. The portal is also decorated with two medallions inside of which there are inscriptions in Kufic Arabic. - The Mausoleum of the Shirvanshahs is of a rectangular shape and crowned with a hexahedral cupola which is decorated from outside with multi-radial stars. The inscription on the entrance doorway indicates the purpose of the building, "Khalilullah I, the greatest Soltan, Great Shirvanshah, the namesake of the divine prophet, the defender of the religion ordered to construct this light burial-vault for his mother and son in 839" (1435–1436). On two drop-shaped medallions in the flannel parts of the portal there are inscriptions with the architect's name - Memar Ali (architect Ali). - The Palace Mosque (1430s) is situated in the lower court of the complex. The laconicism of its prismatic volumes, completed with two slightly pointed cupolas, is shaded by a well-proportioned vertical line of the minaret rising above in the north-eastern corner of the building. There are 2 chapels for prayers in the mosque: a hall of a large size for men and a hall of a small size for women, also a couple of small subsidiary rooms. There is an inscription laid under the stalactite belt of the minaret which reads, "The greatest Soltan Khalilullah I ordered to build this minaret. May Allah exalt the days of his governing and reign. The year of 845" (1441–1442). - Seyid Yahya Bakuvi's Mausoleum is situated in the southern part of the complex. Seyid Yahya Bakuvi was a royal scholar in the court of Shirvanshah Khalilullah. The Mausoleum is of an octahedral shape and covered with an octahedral marquee. It consists of ground and underground parts. The upper part of the Mausoleum served to perform the cult rites, and the lower one housed the sepulchral vault. There are three small lancet windows with a stone bar - shabaka on the southern, eastern and western verges of the Mausoleum. - The Shirvanshahs' Palace complex also includes the portal of Eastern Gates, the so-called "Sultan Murad's Gate" (1585). It was built within the walls of the citadel rather later than all the other constructions of the complex during Ottoman occupation of 1585-1603. The gates were named by them in honor of Sultan Murad III. - The Palace Bath-house is situated on the lowest terrace of the complex. It was discovered in 1939 and dates to 17th century. The archaeological excavations exposed a big bath-house consisting of 26 rooms. On the basis of the surviving remains of the walls of the bath-house one can say that its rooms used to be covered with cupolas and the light penetrated through the openings in the cupolas. The bath-house was semi-underground for keeping the heat in winter and the cool in summer.