A pedestrian wearing a form of PPE (personal protective equipment) of a perspex full-face covering, as a precautionary measure against COVID-19, walks across Oxford Street in central London on June 11, 2020, as non-essential shops prepare to re-open on June 15. Britain's current guidelines on social distancing remain at two metres (2M), but business leaders and some politicians are on Thursday calling for it to be reduced to one (1M), or one-and-a-half (1.5M) metres. (Photo by Justin Tallis/AFP Photo)

A member of staff at Morton & Eden holds an extremely rare early Islamic gold coin on Thursday September 12, 2019, which is expected to fetch £1.4m at auction in London. Measuring a 20mm across, about the size of a modern £1 piece, it is one of the world's rarest and most treasured Islamic gold coins from the first dynasty of Islam, the Umayyad gold dinar dated 105h (723AD). (Photo by Victoria Jones/PA Images via Getty Images)

Girls Aloud: Nicola Roberts, Kimberley Walsh, Sarah Harding and Cheryl Cole at Kimberley Walsh's birthday party hosted by Damian Darkko at Mint Nightclub in London, Britain on November 25, 2006. The Girls Aloud star Sarah Harding has died at the age of 39, her mother has said in a post on Instagram. Issue date: Sunday September 5, 2021. (Photo by Rex Features/Shutterstock)

Faith Lynch (L) and Molly Beck (R) pose for a photo at Hackney Bridge as fans gather to watch a live broadcast of the semi-final match between England and Denmark on July 07, 2021 in London, England. England has reached the semi-finals of the UEFA European Football Championship 2020 hoping to make the final for the first time in the history of the competition. (Photo by Leon Neal/Getty Images)

Nobby the polar bear cools down as he plays in a lake at the Yorkshire Wildlife Park in Doncaster, England, Friday June 17, 2022. A blanket of hot air stretching from the Mediterranean to the North Sea is giving much of western Europe its first heat wave of the summer, with temperatures forecast to top 30 degrees Celsius (86 degrees Fahrenheit) from Malaga to London on Friday. (Photo by Danny Lawson/PA Wire via AP Photo)

A demonstrator with face painted in the colours of the Palestinian flag protests outside the Israeli Embassy in west London July 26, 2014. Foreign ministers from the United States, Europe and the Middle East called on Saturday for an extension of the 12-hour ceasefire between Israel and Hamas in the Gaza Strip, French Foreign Minister Laurent Fabius said. (Photo by Luke MacGregor/Reuters)

These are the ambitious plans which suggest skyscrapers of the future may house an entire city. The Endless City project is an award-winning proposal by sure Architecture, who propose turning skyscrapers into complete ecosystems. London is the proposed city for the mixed-use tower – which would feature huge ramps linking different sections of the structure. The company, whose design won the SkyScrapers and SuperSkyScrapers Competition, insist the structure would be a great space-saver in dense cities which have previously spread outwards rather than upwards. (Photo by Caters News)

Pedestrians and traffic cross Tower Bridge as viewed through a glass viewing platform on the high-level Walkways during a preview to launch the new viewing experience at the Tower Bridge Exhibition centre in London on November 10, 2014. The new glass flooring at the Tower Bridge Exhibition 42 metres above the river Thames will allow visitors to gaze down on the bridge and river and allow them to experience the bridge opening from above. (Photo by Andrew Cowie/AFP Photo)