The Abraj Al-Bait is a government-owned complex of seven skyscraper hotels in Mecca, Saudi Arabia. These towers are a part of the King Abdulaziz Endowment Project that aims to modernize the city in catering to its pilgrims. The central hotel tower, the Makkah Royal Clock Tower, has the world's largest clock face and is the third-tallest building and fifth-tallest freestanding structure in the world.
The building complex is metres away from the world's largest mosque and Islam's most sacred site, the Great Mosque of Mecca. The developer and contractor of the complex is the Saudi Binladin Group, the Kingdom's largest construction company. It is the world's most expensive building with the total cost of construction totalling US$15 billion.
The complex was built after the demolition of the Ajyad Fortress, the 18th-century Ottoman citadel on top of a hill overlooking the Grand Mosque.
According to en.wikipedia