History
Brief Overview
1453: Conquest of Constantinople, known today as Istanbul, by Sultan Mehmed II
1459: Sultan Mehmed II the Conqueror orders the construction of the 'New Palace', which is now the Topkapi Palace
1465: Construction of Topkapi Palace is completed
1509: Extensive renovations and expansions take place due to damage from earthquakes
1529: During the reign of Suleyman I, the second gate is completed.
1665: Severe fire destroys large parts of the palace; renovation works are initiated
1853: The palace ceased to be used as a royal residence. Under Sultan Abdulmejid, the Ottoman elite moves to the newly built Dolmabahce Palace; Topkapi becomes an accommodation for ranked officers
1924: Topkapi Palace is converted into a museum
1985: UNESCO declares Topkapi Palace a World Heritage Site

History of Topkapi Palace
The Topkapi Palace gets its name from the Turkish word for "cannon gate". The grand palace served as both the former seat of government and the home of Ottoman rulers.
Sultan Mehmet the Conqueror ordered the construction of the palace six years after Constantinople was conquered in 1453. He chose this strategic location because it had a wide view of the Sea of Marmara, Golden Horn and Bosphorus; making it well-protected against enemies. It was also built on the site of Byzantium's Acropolis. The walls built by Byzantines protected against dangers coming from the water; starting from Topkapi's eastern corner along the coast of Sea of Marmara to Constantinople's Walls.
The first part of building was completed in 1468 but it continued to be enlarged until 1478. All Ottoman rulers added their own expansions and enhancements over time. By early 18th century, the palace achieved its current form. However, when Sultan Abdulmejid I decided to build a new palace in European style and eventually moved his court to Dolmabahce Palace in 1856, Topkapi Palace lost its importance.
Since 1924, it has served as a museum open to the public. Today, it is one UNESCO World Heritage Site and one Istanbul's most famous landmarks.