'World's most expensive street' where billionaires' mansions now lie in ruins

It was once the most expensive street in the world, known as "Billionaire's Row" and just a short distance from some of London's most prestigious areas like Hampstead and Highgate.

Home to more than 60 enormous mansions, worth a combined hundreds of millions of pounds at the very least, The Bishops Avenue in London has an extraordinary history. But while many of the palatial homes are still lived in, others lie empty and seemingly abandoned, while others have been turned into care homes.

The owners of many of these mansions are a mystery, with ownership in many cases registered to companies based in off-shore tax havens and practically impossible to trace without forensic accountants. However, some owners are known, with the Saudi royal family behind an imposing collection of mansions called "The Towers", which they bought in the 1980s in case Saddam Hussein's Iraq invaded.

Another, Heath Hall, was owned by a Czech tycoon and has been rented out by stars including Justin Bieber and Salma Hayek.

Despite their dilapidated state, the houses are still individually worth tens of millions of pounds, and are owned by the sort of unimaginably wealthy people who can just leave such an asset lying unused.

Each house is remarkable in its own way. One was once the fortified home of Salman Rushdie, who lived here in secret with 24-hour police protection after the state of Iran put a death warrant on his head.

Another was home to a Nigerian politician - it was seized by squatters after his death in 2007 and burned down.

Another of the houses, owned by an asset manager, was the scene of one of London's biggest robberies in 2006, where £2m of items were reportedly stolen.

And yet another is where contestants on The Apprentice stay during the filming of the BBC series. It reportedly has eight bedrooms, nine bathrooms and is worth £17 million.

The history of the street is fascinating and mysterious. It was already being called "Millionaire's Row" by the 1930s, when the first handful of mansions were already in place.

Sugar magnate William Lyle was among its first residents, and was an early owner of Heath Hall, which Bieber reportedly rented more recently for £27,000 a week. The Sultan of Brunei, once the world's richest man, owned a house here too.

But the people behind many more are impossible to trace. Business Insider reports that 60% of them are owned by "hard-to-scrutinise shell corporations registered in foreign tax havens like the Bahamas, Panama, and the British Virgin Islands."

While hiding their wealth is clearly a motivation for some of the street's property owners, hiding altogether is what drives others.

"One gentleman from Russia never leaves The Bishops Avenue. He won't even go around the corner," a local property agent told Business Insider.

Other people who have owned property here include a former Lebanese prime minister; the last king of Greece, Constantine II; and the publisher and businessman Richard Desmond.

Aristos Constantinou, the Greek-Cypriot fashion tycoon, was shot dead here, and another former owner, who once tried to organise a coup in Equitorial Guinea, died in a freak accident by falling down the stairs of another of his mansions in London's Holland Park.

One, called Toprak Mansion, is a 30,000 sq ft mansion built by the Turkish entrepreneur Halis Toprak in the 1990s, which achieved the highest sale price seen in Britain in 2008, when it was sold for £50 million to a Kazakhstani billionaire.

It had a Turkish bath that could hold 20 people. It was bought in 2013 by a company based in the British Virgin Islands for £66 million, The Sunday Times reports.

"The Bishops Avenue is so interesting that you could say if it didn't exist it would need to be invented," Trevor Abrahmsohn, a luxury property consultant, told The Sunday Times, adding: "A house starts off being owned by the Savile Row-tailored businessmen with posh voices, and ends up being run by the Mujahideen."

While many of the mansions lie in ruins, others have been developed.

Hammerson House was opened as a care home in 2021, replacing one of the huge homes, while a few doors up another care home is set to open in 2025 as a luxury complex for older people with 93 flats over six storeys.

And The Towers, the enormous collection of properties bought by the Saudi royal family in the late 1980s, have now been sold to a developer with the aim reportedly being to turn them into luxury flats.