The world's second largest house can be found in Surrey, 40 km away from London. It’s called Updown Court and has an area of 23 hectares (equal to 23 soccer fields). To give an order of magnitude, Updown Court is bigger than the Hampton Court Palace and Buckingham Palace together. Its construction began in 1924 with a California neoclassical style and summing up a cost of more than $80 million, becoming the most expensive private property in the world. Annual maintenance of Updown Court costs about one million euros. For this reason, its owner, Leslie Allen-Vercoe, had to sell their most expensive property because he could not keep or maintain it. Irish Nationwide Bank kept the property and sold it to Lakshmi Mittal for 40 million euros. It is currently valued at 104 million euros.
Updown Court has a total of 123 rooms, of which 55 are bedrooms, each decorated in a different style. It also has 27 bathrooms decorated with marble that contains over 30 different types of ornaments imported from Italy. It also has a squash court, a wine cellar with 3,000 bottles... Its underground garage is capable of accommodating a small collection of luxury cars with up to eight limousines. It also has a total of 5 pools; Two of them enclosed in the gardens and another one is found on the roof and boasts spectacular views. The other two are covered and their access has to be by a private elevator, which also leads to the sauna, a beauty salon and a dressing room. This mansion also contains a bowling alley, a billiard room and a cinema with 50 seats with a private bar to give the best show and entertainment to its guests.
The main residence has 4,645 m of inhabitable space divided into 4 different floors. In one of them we find a mosaic with a gold leaf of 24 carat. In the main house there are a total of 22 rooms and the entrance is a design made with the same marble that was used in the construction of the Taj Mahal. The two penthouses, which are located at the top and are totally independent, overlook the 250,000 m2 of private gardens and woodlands. In addition to the main residence, it also has 2 guesthouses, which consist of 9 suite rooms with their 9 bathrooms respectively.
Updown Court also has a safety flag, where the panic room is located, fully equipped to protect everyone in the house in case of an assault with a deadly weapon. It also has 65 high-tech cameras to provide and ensure safety at all times.

http://en.wikipedia.org/wiki/Updown_Court

http://www.dailymail.co.uk/news/article-2049839/Updown-Court-fetches-just-35m-years-market.html

http://www.rightmove.co.uk/property-for-sale/property-32881547.html

http://www.luxuo.com/most-expensive/updown-court-most-expensive-mansion-in.html

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