The cribs belonging to Oprah, Bill Gates, Britian's royal family and the Sultan of Brunei top the list
484,000 sq. ft.: Windsor Castle, Berkshire, England. One of the official residences of the Queen; 1,000 rooms on 13 acres.STEFAN WERMUTH
66,395 sq. ft.: Estate in Sagaponack, N.Y., built by billionaire Ira Rennert; on 63 acres, it has 29 bedrooms, 39 bathrooms.
66,000 sq. ft.: Bill Gates’ home on five-acre property in Medina, Wash.; seven bedrooms, 24 bathrooms, six kitchens.Anthony Bolante
60,000 sq. ft.: 18-bedroom waterfront estate in Palm Beach, Fla., bought from Donald Trump by Russian billionaire Dmitry Rybolovlev.
56,000 sq. ft.: The Aspen, Colo., Hala Ranch, once owned by Saudi Prince Bandar bin Sultan bin Abdulaziz; 16 bathrooms, 15 bedrooms.Steve Mundinger
55,000 sq. ft.: White House in Washington D.C., home to the U.S. president; 132 rooms, including 35 bathrooms, on 18 acres.JIM YOUNG
35,000 sq. ft.: Five-floor residence, being built in downtown Mumbai for Indian billionaire Mukesh Ambani; the home will sit atop a 19-storey skyscraper bedecked with hanging gardens.
28,000 sq. ft.: Mansion in London, England, built by Turkish businessman Halis Toprak and later sold to a Kazakhstan billionaire; seven bedrooms, and a Turkish bath that seats 20.
23,000 sq. ft.: Oprah Winfrey’s main home in Santa Barbara, Calif., on 42-acre property, with 14 bathrooms, six bedrooms.
65,000 sq. ft: The largest house in Canada is in Haileybury, Ont., and sits on 43 acres of land and can accommodate a golf course and a 40 ft. yacht.