Description: Biggest palace in the world.
Istana Nurul Iman contains 1,788 rooms, 257 bathrooms, and a floor area of 2,152,782 square feet (200,000 m²).
Built in 1984
The Istana Nurul Iman palace is the official residence of the Sultan of Brunei, . The palace is located on a leafy, riverside sprawl of hills on the banks of the Brunei River directly south of Brunei’s capital, , no more than a few miles outside the city center. It is the largest residential palace in the world and the world’s largest residence of any type. It was designed by the National Artist of the for Architecture, Leandro V. Locsin and built by Filipino firm, Ayala International.
Although the palace is hidden from public view through artful landscaping, satellite views provided by programs such as Google Earth, have increased the public knowledge of the palace’s layout. Such images have relayed the existence of two large buildings in the center of the palace and five smaller buildings either adjacent to or nearby the palace center.
Istana Nurul Iman contains 1,788 rooms, 257 bathrooms, and a floor area of 2,152,782 square feet (200,000 m²).  Amenities include 5 swimming pools, and an air conditioned stable for the Sultan’s 200 polo ponies, a 110-car garage, a banquet hall that can be expanded to accommodate up to 4,000 guests, and a mosque accommodating 1,500 people.  The palace was built in 1984 at a cost of around $1.4 billion USD and has 564 chandeliers, 51,000 light bulbs, 44 stairwells, and 18 elevators.  It is also a home to a car collection that includes custom-made Ferraris and Bentleys as well as 165 Rolls Royces. Its golden domes, designed by Filipino architect Leandro V. Locsin, and vaulted roofs echo Islamic and Malay architectural influences
The palace is used for all State functions. It is both the seat of Brunei’s government and the location of the prime minister’s office. In addition to Audience and State Rooms, there is a Throne Chamber used for various occasions such as the proclamation of the Crown Prince and the annual Birthday Investiture.
The palace is not open to the public except on the annual Islamic celebration of Hari Raya Idulfitri (the festival at the end of the Muslim fasting month) when the palace receives about 110,000 visitors over a three-day period where they receive compliments such as food for visiting from the 2nd to 4th day of Hari Raya (Syawal)
Istana Nurul Iman is undisputedly the world’s largest residential and administrative palace currently in use for state functions, and at 2,152,782 square feet, Istana Nurul Iman certainly has more building floorspace than any other palace in the world.