The Galata Tower

 The Galata Tower (Galata Kulesi in Turkish) — called Christea Turris (the Tower of Christ in Latin) by the Genoese — is a medieval stone tower in the Galata district of Istanbul, Turkey, just to the north of the Golden Horn. One of the city's most striking landmarks, it is a high, cone-capped cylinder that dominates the skyline and affords a panoramic vista of Old Istanbul and its environs. 
_Description_
       The nine-story tower is 66.90 meters tall (62.59 m without the ornament on top, 51.65 m at the observation deck), and was the city's tallest structure when it was built. The elevation at ground level is 35 meters above sea-level. The tower has an external diameter of 16.45 meters at the base, an 8.95 meters diameter inside, and walls that are 3.75 meters thick.
There is a restaurant and café on its upper floors which commands a magnificent view of Istanbul and the Bosphorus. Also located on the upper floors is a nightclub which hosts a Turkish show. There are two operating elevators that carry visitors from the lower level to the upper levels. Entrance to the tower costs 10 TL (Turkish Lira). 
_History_
       The tower was built as Christea Turris in 1348 during an expansion of the Genoese colony in Constantinople. It was the apex of the fortifications surrounding the Genoese citadel of Galata. The current tower should not be confused with the old Tower of Galata, an original Byzantine tower, named Megalos Pyrgos, which controlled the northern end of the massive sea chain that closed the entrance to the Golden Horn. That tower was on a different site and was largely destroyed during the Fourth Crusade in 1204.
       The upper section of the tower with the conical cap was slightly modified in several restorations during the Ottoman period when it was used as an observation tower for spotting fires.
       According to the Seyahatname of Ottoman historian and traveller Evliya Çelebi, in circa 1630-1632, Hezarfen Ahmet Çelebi flew as an early aviator using artificial wings for gliding from this tower over the Bosporus to the slopes of Üsküdar on the Anatolian side, nearly six kilometres away. Evliyâ Çelebi also tells of Hezarfen's brother, Lagari Hasan Çelebi, performing the first flight with a rocket in a conical cage filled with gunpowder in 1633.
       Starting from 1717 the Ottomans began to use the tower for spotting fires in the city. In 1794, during the reign of Sultan Selim III, the roof of the tower made of lead and wood and the stairs were severely damaged by a fire. Another fire damaged the building in 1831, upon which a new restoration work took place. In 1875, during a storm, the conic roof on the top of the building was destroyed. The tower remained without this conic roof for the rest of the Ottoman period.
Many years later, in 1965-1967, during the Turkish Republic, the original conical cap was restored. During this final restoration in the 1960s, the wooden interior of the tower was replaced by a concrete structure and it was commercialized and opened to the public.
       From the top of the tower, the first French panorama painter Pierre Prévost drew in 1818 his "Panorama de Constantinople" later exposed in Paris in 1825.
The panorama image shown below is composed of ten photos taken from the Galata Tower by the photographic firm of Sébah & Joaillier, and is most likely to have been taken in the 1880's.
       Panoramic view of the Golden Horn in Istanbul, as seen from the Galata Tower. The Galata Bridge can be seen in the center of the picture. The Seraglio Point (Sarayburnu) where the Topkapı Palace is located is seen at the left tip of the historic peninsula; followed by (left to right) the Hagia Sophia, the Sultan Ahmed (Blue) Mosque, the Yeni (New) Mosque near the Galata Bridge, the Beyazıt Tower rising high in the background, and the Süleymaniye (Suleiman the Magnificent) Mosque at far right, among others. The Sea of Marmara and the Princes' IslandsKadıköy (ancient Chalcedon) on the Asian side of the city can be seen. Behind the Galata Bridge, towards the horizon, the Column of Constantine (which was surrounded by iron bars for restoration at the time of this photo) rises.