The Süleymaniye Mosque is an Ottoman imperial mosque located on the Third Hill of Istanbul, Turkey. The mosque was commissioned by Suleiman the Magnificent (r. 1520–1566) and designed by the imperial architect Mimar Sinan. It is one of the best-known sights of Istanbul and is considered a masterpiece of Ottoman architecture and one of Mimar Sinan's greatest works. It is the largest Ottoman-era mosque in the city.
Like other Ottoman imperial foundations, the mosque is part of a larger külliye (religious and charitable complex) which included madrasas, a public kitchen, and a hospital, among others. Behind the qibla wall of the mosque is an enclosed cemetery containing the separate octagonal mausoleums of Suleiman the Magnificent and his wife Hurrem Sultan (Roxelana).
The courtyard, measuring around 47 by 57 metres, is of exceptional grandeur with a colonnaded peristyle supported by tall columns of marble, granite and porphyry.
Four minarets occupy the four corners of the courtyard. The two taller ones have three balconies and rise to a high 76 m.
The Walls of Constantinople are a series of defensive stone walls that have surrounded and protected the city of Constantinople (today Istanbul) since its founding as the new capital of the Roman Empire by Constantine the Great. With numerous additions and modifications during their history, they were the last great fortification system of antiquity, and one of the most complex and elaborate systems ever built. They were also the largest and strongest fortification in both the ancient and medieval world.
Initially built by Constantine the Great, the walls surrounded the new city on all sides, protecting it against attack from both sea and land. As the city grew, the famous double line of the Theodosian Walls was built in the 5th century. Although the other sections of the walls were less elaborate, they were, when well-manned, almost impregnable for any medieval besieger.