principle of increased seclusion over time was reflected in the construction style and arrangements of various halls and buildings. The architects had to ensure that even within the palace, the sultan and his family could enjoy a maximum of privacy and discretion, making use of grilled windows and building secret passageways. Later sultans made various modifications to the palace, though Mehmed II's basic layout was mostly preserved. The palace was significantly expanded between 1520 and 1560, during the reign of Suleyman the Magnificent. The Ottoman Empire had expanded rapidly and Suleyman wanted his residence to reflect its growing power. The chief architect in this period was the Persian Alaüddin, also known as Acem Ali. He was also responsible for the expansion of the Harem. In 1574, after a great fire destroyed the kitchens, Mimar Sinan was entrusted by Sultan Selim II to rebuild the damaged parts of the palace. Mimar Sinan restored and expanded not only the damaged areas, but also the Harem, baths, the Privy Chamber and various shoreline pavilions. By the end of the 16th century, the palace had acquired its present appearance. The palace is an extensive complex rather than a single monolithic structure, with an assortment of low buildings constructed around courtyards, interconnected with galleries and passages. Few of the buildings exceed two stories. Seen from above, the palace grounds are divided into four main courtyards and the harem. The first courtyard was the most accessible, while the fourth courtyard and the harem were the most inaccessible. Access to these courtyards was restricted by high walls and controlled with gates. Apart from the four to five main courtyards, various other small to mid-sized courtyards exist throughout the complex. Estimates of the total size of the complex varies from around to . To the west and south the complex is bordered by the large imperial flower park, known today as Gülhane Park. Various related buildings such as small summer palaces (kasır), pavilions, kiosks (köşk) and other structures for royal pleasures and functions formerly existed at the shore in an area known as the Fifth Courtyard, but have disappeared over time due to neglect and the construction of the shoreline railroad in the 19th century. The last remaining seashore structure that still exists today is the Basketmakers' Kiosk, constructed in 1592 by Sultan Murad III. Imperial Gate The main street leading to the palace is the Byzantine processional