It has been likened to a monster, an oil rig – and the Parthenon. Now, for its 40th birthday, the astonishing London landmark has joined the Open House festival, to grant admirers a rare look around the inside

In his 2012 book A New Kind of Bleak, the critic Owen Hatherley called it “monstrous, compelling” and utterly messed-up. Back in the 1980s, a then Prince Charles suggested it had been inspired by a North Sea oil rig. But none of this stopped it from becoming, in 2011, the youngest ever building to be given Grade I-listed status in the UK.

And now, as part of its 40th anniversary celebrations, the Lloyd’s building will open to the public for the first time since 2014 for one day only during London’s Open House festival. The iconic building in the heart of the financial district was designed by architect Richard Rogers to house the global insurance marketplace. Its futuristic facade has been a celebrated part of the City of London skyline since it opened in 1986, but the interior is rarely seen by the public. Visitor galleries with a view of the trading floor have long been shut for security reasons.

Panic about antisocial behaviour and theft has broken through from social media to boardrooms and diplomatic circles

“Just visit London and you’ll see that it’s filled with crime,” the tech billionaire Elon Musk said as he was beamed into Tommy Robinson’s far-right rally in the UK capital last September.

The comments by the SpaceX and Tesla boss, part of a roving speech that was later condemned by the UK government, added to a growing wave of anti-London disinformation that has spread in recent months. That includes Donald Trump’s notorious comments of London “no-go zones” and Nigel Farage’s warnings against wearing jewellery after 9pm in the West End.

A decision on China’s controversial mega-embassy in London is imminent, with Chinese officials and British diplomats in Beijing anxiously awaiting the outcome of a planning application that could soon be approved. MPs from across the political spectrum have condemned the proposal, but UK security services say they can contain the espionage risks posed by the expanded site, which sits close to sensitive data cables linking to the City of London

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Allowing entry on the basis of self-identification of gender rather than biological sex is unlawful, high court told

Rules permitting trans women to share female changing facilities and swim in a women-only pond are discriminatory and unlawful, the high court has heard.

The City of London Corporation is breaching equality legislation by allowing trans people to use the single-sex ponds on Hampstead Heath, according to a claim brought by the rights group Sex Matters. It is seeking permission to challenge the admission regulations.