London is famed for its lavish 'iceberg' basements, but mega-wealthy property owners outside the capital are just as eager to dig down, judging by this amenity-loaded mansion in Surrey, UK. The mansion has all the trappings the super-rich demand, including a marble-floored leisure reception area, a top-of-the-range gym and an elegant tasting room.

The 70-room country pile was for sale via Sotheby's International Realty in May 2025 for £29 million ($38.3m), before it had even been built. In fact, these images are all CGI designs, showing prospective buyers exactly what to expect if they splashed out on the place.

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