It is thought there will also be a large wine cellar, an art storage room, gym facilities and male and female changing rooms at the house owned by David Graham, a Canadian who according to reports made hundreds of millions of pounds when he sold his cable television business.
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Police are investigating whether a Land Rover Defender found burnt out in West Horsley was involved in Tuesday night's ram raid.
The work, called Gift Horse, replaces the giant blue cockerel that previously sat on the plinth.
50 of the country's worst pollution blackspots are in the capital. Many in places you may visit every day.