In this Wednesday, March 18, 2015 photo, limestone quarry workers walk through a cloud of dust spewed into the air by rotor blades of the stone-cutting machinery in the desert of Minya, southern Egypt. Around 45,000 people, including children, work in an estimated 1,500 quarries, digging out stones that later will be used in construction or powdered to be used by pharmaceutical and ceramic companies. (Photo by Mosa'ab Elshamy/AP Photo)

Central Bangkok and the Chao Phraya River are seen from an abandoned skyscraper in Bangkok April 19, 2015. The abandoned building, known as Satorn Unique, dubbed the “ghost tower” was destined to become one of Bangkok's most luxurious residential addresses but construction was never completed as the Thai economy was hit during the 1997 Asian Financial Crisis. Now, many travellers visit and explore 49-storey skyscraper. (Photo by Athit Perawongmetha/Reuters)

Wind turbines stand in the Baltic 1 offshore wind farm on April 29, 2011 in the Baltic Sea near Zingst, Germany. Baltic 1, a project of German energy utility EnBW that includes 21 turbines rated at 2.3 megawatts each, will be Germany's first commercial offshore wind farm once it officially begins operation on May 2. Germany has thus far lagged in offshore wind farm construction when compared to neighbors like Great Britain and Denmark, though German Chancellor Angela Merkel has vowed to invest heavily into offshore wind farms as part of an overall policy to encourage renewable energy production. (Photo by Joern Pollex/Getty Images)

A concept illustration of the world's first forest in the sky, the Bosco Verticale green twin towers currently under construction in Milan, Italy. Towering over the city skyline the world's first forest in the sky will be a sight to behold. With tree equal to one hectare of forest spanning 27 floors these 365 and 260 foot emerald twin towers will be home to an astonishing 730 trees, 5,000 shrubs and 11,000 ground cover plants. (Photo by Boeri Studio)

Construction cranes stand on the Unstrut Valley high-speed railway bridge on March 19, 2012 near Karsdorf, Germany. The Unstrut bridge, which is 2,668m long (about 1.6 miles), is among 38 bridges and 26 tunnels German state rail carrier Deutsche Bahn is building along a new ICE high-speed railroad connection between Nuremberg, Erfurt, Halle, Leipzig and Berlin in a multi-billion Euro project across eastern Germany called the German Unity Transportation Project (Verkehrsprojekt der Deutschen Einheit). (Photo by Sean Gallup/Getty Images)

The Mano de Desierto is a large-scale sculpture of a hand located in the Atacama Desert in Chile, 75 km to the south of the city of Antofagasta, on the Panamerican Highway. The nearest point of reference is the “Ciudad Empresarial La Negra” (La Negra Business City). The sculpture was constructed by the Chilean sculptor Mario Irarrázabal at an altitude of 1,100 meters above sea level. Irarrázabal used the human figure to express emotions like injustice, loneliness, sorrow and torture. Its exaggerated size is said to emphasize human vulnerability and helplessness. The work has a base of iron and cement, and stands 11 metres (36 ft) tall. Funded by Corporación Pro Antofagasta, a local booster organization, the sculpture was inaugurated on March 28, 1992.

A participant from Indonesia waits to perform a dance during the last day of World Culture Festival on the banks of the river Yamuna in New Delhi, India, March 13, 2016. The festival opened on the banks of the Yamuna River in the Indian capital Friday despite concerns the sprawling construction of roads, ramps and pontoon bridges would irreparably damage the river's floodplains. (Photo by Adnan Abidi/Reuters)

Malian workers haul out a boat they use to carry sand collected from the river bed during a routine maintenance on October 7, 2018, in the port of Bamako. Increasing construction in the Malian capital has boosted the demand for bricks made out of high-quality Niger River sand. (Photo by Michele Cattani/AFP Photo)