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)

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)

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)

Japan's ON-ART Corp's staff repaints the company's eight metre tall man-operated walking dinosaur robot “TRX03” at the company's studio in Tokorozawa, Japan, December 6, 2016. (Photo by Toru Hanai/Reuters)

A Saddle-billed Stork is seen in Amboseli National park, Kenya, February 10, 2016. (Photo by Goran Tomasevic/Reuters)

The Zhangjiajie National Forest Park is a unique national forest park located in Zhangjiajie City in northern Hunan Province in the People's Republic of China. It is one of several national parks within the Wulingyuan Scenic Area.

Parc Astérix is a theme amusement park in France, based on the stories of Asterix (by Albert Uderzo and René Goscinny). Situated approximately 35 km (22 mi) north of Paris and 32 km (20 mi) from Disneyland Resort Paris, in Plailly in the département of Oise, it opened in 1989. The park is operated by Compagnie des Alpes.