The Dh84m traditional London home with an oligarch's upgrade

London has earned a reputation as a magnet for billionaires from around the globe in recent years – from Russian oligarchs leaving their homeland either in friendly or unfriendly circumstances, to other emerging market business moguls and Silicon Valley tech entrepreneurs.

Although the sources of their riches are diverse, one thing they share is a strong desire to retain them. That is, after all, one of the main reasons they end up in the UK’s capital, which has generous tax rules for those with a “non-domicile” status.

With this in mind, many traditional properties in the capital have been upgraded in recent years with a series of more modern features.

The Tower House in the prestigious St John’s Wood area of London is a good example of this. The detached home was built in 1850 and was one of five homes on Carlton Hill built as test cases for new architectural designs in what became known as the Battle of the Styles.

It has recently undergone an extensive refurbishment by the Chelsea-based antique furniture specialist Tarquin Bilgen and by Mathew Bray Decorative Arts studio. The £18.5 million (Dh83.9m), 8,956 square foot home is split over six main levels. The ground floor contains an entrance hall, study and dining room leading into a full-width drawing room that opens onto a large, upper terrace overlooking the garden.

The lower-ground floor has an open-plan kitchen/breakfast room with Poggenpohl appliances leading onto the lower terrace as well as a cinema, ­family room and an independent flat with a bedroom and ­living space for a nanny or housekeeper. The three upper floors contain a total of five bedrooms – four of which are en suite, including a master bedroom with two separate dressing room areas.

The basement, meanwhile, is the space that could most appeal to the billionaire buyer. It has a leisure complex comprising a 30-foot-long pool, a sauna, steam room and gym.

It also houses storage space including a “strong room” that contains a safe and a secure area that can be sealed off in case of any unwanted visitors. The house also has an extensive security system that includes alarms, panic buttons and CCTV cameras.

It is being sold by joint letting agents Savills and Russell ­Simpson.

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