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)

Kale grows at Kajodlingen farm in Gothenburg, Sweden, September 28, 2016. They are doing it on the rooftops, on tower block balconies and even on a disused railway: Swedes have discovered a passion for urban gardening as a way of growing fresh food and getting back in touch with nature. Part of a global movement, an increasing number of Swedish city-dwellers are growing their own in window boxes and allotments or are visiting public gardens built in or on industrial or office spaces. (Photo by Maxim Shemetov/Reuters)

A man sleeps between tombstones in front of his single-room home on a hot night in the Cairo Necropolis, Egypt, October 13, 2015. In the sprawling Cairo Necropolis, known as the City of the Dead, life and death are side by side. Amid a housing crisis in Egypt, and with the population of greater Cairo estimated at about 20 million, people count themselves lucky to have a place to call home in the graveyards that date back hundreds of years. (Photo by Asmaa Waguih/Reuters)

The interior of a house is damaged after an earthquake in Imphal, capital of the northeastern Indian state of Manipur, Monday, January 4, 2016. Five deaths have been reported from in and around Imphal due to falling debris. Imphal has a population of 270,000, and people were jolted from their sleep and ran out of their homes in panic. (Photo by Bullu Raj/AP Photo)

A boy dressed as Lord Krishna is pictured while Hindu devotees march on the streets to celebrate Janmashtami festival, which marks the birth anniversary of Lord Krishna, in Dhaka, August 14, 2017. (Photo by Mohammad Ponir Hossain/Reuters)

Bangladeshi relatives wail near bodies of victims after a river ferry carrying about 100 passengers capsized Sunday after being hit by a cargo vessel,in Manikganj district, about 40 kilometers (25 miles) northwest of Dhaka, Bangladesh, Sunday, February 22, 2015. (Photo by A. M. Ahad/AP Photo)

Nasoin Akhter, 15, has her makeup done at a beauty parlor on the day of her wedding to a 32-year-old man, August 20, 2015, in Manikganj, Bangladesh. In June of this year, Human Rights Watch released a damning report about child marriage in Bangladesh. The country has one of the highest rates of child marriage in the world, with 29% of girls marrying before the age of 15, and 65% of girls marrying before they turn 18. (Photo by Allison Joyce/Getty Images)

Bangladeshi farmers carry harvested produce in a cultivated field ahead of the 14 May World Farmers Day in Chittagong, Bangladesh on May 12, 2022. (Photo by Mohammad Shajahan/Anadolu Agency via Getty Images)