Istanbul New Palace / Topkapı Palace was established on an area of 70 decares at the end of the historical peninsula in Istanbul, in a position overlooking the Marmara Sea, Asia-Üsküdar and the Golden Horn, thus dominating the city from all directions. After the conquest of Istanbul by the Ottomans, the construction started with garden arrangements and pavilions in Sarayburnu, which was called Zeytinlik, and continued with the walls called Sûr-ı Sultânî (Kal‘a-i Sultânî). XIX to Topkapi Palace. Various additions were made in each period until the middle of the century. The palace, which is shaped according to the state organization and usage needs, has many architectural and decorative features. In general, it has a structure articulated with each other with a horizontal extension in accordance with the land it is located on. The information about the start and end dates of the building in the sources of the period are different from each other. Since the date on the Bâb-ı Hümâyun is 883 (1478), it can be assumed that the construction started before this date and probably in 1465. Many years after the palace construction, probably XVIII. It was called Sarây-ı Cedîd-i Âmire due to the old palace in Beyazıt until the 16th century, and then the name of the mansion called Collective Gate was started to be used because of the name of the mansion, which is located on the sea side and the balls were placed on the sides.

The palace has three large gates, called the Iron Gate and Otluk Gate, and five service gates (seat doors), the largest of which is the Bâb-ı Hümâyun, which is the main entrance gate, on the city walls of the Byzantine period. The first door, the Bâb-ı Hümâyun, is a two-storey mansion door and the inscription above it is Ali b. It is signed by Yahya as-Sufi. There were seven windows in the lower row and six windows in the upper row on the facade of the mansion. XIX. The upper floor of the building, which was damaged by fire and earthquake in the second half of the century, collapsed. Based on the pre-Ottoman walls of the city, it is accepted that the main gates were built together with the Sûr-ı Sultânî surrounding the palace (see BÂB-ı HÜMÂYUN). It can be said that Topkapı Palace consists of four sections in terms of organization: Service and protection area (Bîrun), administrative center (Dîvân-ı Hümâyun), education area (Enderun) and private living area (Harem).
Topkapi Palace is shaped around three main courtyards and three abidevi gates. The first door is the Bâb-ı Hümâyun, the second is Bâbüsselâm, the third is Bâbüssaâde. The big square between Bâb-ı Hümâyun and Bâbüsselâm is the section where the units and employees that meet the needs of the palace are located. In addition, it shows the feature of a square where people and soldiers can enter and exit. It is from written sources that it is an area where the retinues and janissaries of the statesmen attending the ceremony, especially during the juls and eid ceremonies, await. century miniature works can be identified. With this function, the first courtyard is the area where the state center is open to the military and the public, and is important in terms of showing that the sultan did not want to separate his living space from the city, although it was surrounded by walls. On the way from the Bâb-ı Hümâyun towards Bâbüsselâm, there were the hospital of the palace (Enderun Hospital), service buildings such as a water closet and bakeries on the right. On the left front was an area where firewood to be used in each part of the palace was piled. In the continuation of this part, there was the Hagia Eirene Church, which was inherited from the Byzantine period and used as a forge after the conquest of Istanbul, and the warehouse. The Dâvî Kasrı, which is closer to the second gate, was in the form of a small mansion with an octagonal plan and tower structure and was important in terms of its function. People who wanted to convey their problems to the court and ruler would submit their petitions to the officer in this mansion. In the first courtyard, there were officials who provided the needs of the palace without the need for city tradesmen. According to İsmail Hakkı Uzunçarşılı, people from the clergy class such as the matbah-ı amire emi, the chief surgeon, the chief surgeon, the khhalbaşı and the sultan’s teacher were the people of Bîrun. The bakeries were called hospitals, nakkaşhane, architects hearth, mehterhane and İstabl-ı âmire Bîrun section. This classification should be accepted as the general structuring of the palace organization, but it should be taken into account that there may be different applications from time to time. According to this classification, all parts except Enderun and Harem are considered as Bîrun.
Babu Selam gate.
Bâbüsselâm was the entrance gate with two towers and two fronts at the entrance of the second courtyard, and it was the place where the state ceremonies started. The towers on top of the building, which consists of two intertwined doors and rooms between the doors, attracted the attention of the researchers. The formal characteristics of the towers are based on the observations of Suleiman the Magnificent during the European expedition and suggest that they were added during the renovation on the gate. Nevertheless, Gülru Necipoğlu, who conducted an extensive study on Topkapı Palace, thinks that the towers were built together with the walls during the reign of Sultan Mehmed the Conqueror. In the Dîvân-ı Hümâyun meetings, doorman chiefs and sergeants welcomed statesmen in front of Bâbüsselâm. The janissary lord would arrive early on the days of the divan, where he waited for the viziers to arrive. Every vizier coming from small to old one would wait for the one on top, and when he came, they were greeted mutually by the salutation sergeants. After this ceremony held in front of Bâbüsselâm in the early morning, statesmen would enter and go to the council accompanied by the sergeant and janitors. The officers working for the statesmen would not enter, they would wait outside the door. The envoys sent to the Ottoman Empire came with a very crowded entourage, most of the entourage would accompany only to Bâbüsselâm, and again outside this door, in the first courtyard, they waited for the end of the ambassador’s meeting. No one except the ruler entered the gate by horse, so the first courtyard was the part where the horses and caregivers of the arrivals were also waiting.