The Maijishan Grottoes are a series of 194 caves cut in the side of the hill of Majishan in Tianshui, Gansu Province, northwest China. This example of rock cut architecture contains over 7,200 Buddhist sculptures and over 1,000 square meters of murals. Construction began in the Later Qin era (384-417 CE).

A 70-metre-long Noah's Ark replica constructed of steel and American cedar on March 31, 2005 in Schagen, Netherlands. (Photo by Michel Porro/Getty Images)

A construction worker sweeps up as the final touches are completed on “Comedy Carpet” by British artist Gordon Young, the latest art installation on Blackpool's promenade on October 7, 2011 in Blackpool, England. (Photo by Christopher Furlong/Getty Images)

In this January 8, 2015 photo, a monk Kenmyo Muta bows at the condominium construction site and the gate of Sengakuji temple in Tokyo. The “47 ronin” samurai who inspired the long-loved saga of loyalty and honor eulogized in films, books and plays are fighting a new kind of battle in urban Japan. An apartment complex is going up next to the curved tile-roofed Sengakuji temple where the three-century-old graves of the ronin, or masterless samurai, lie. The banner reads: “We only hope to protect landscape of Sengakuji temple”. (Photo by Eugene Hoshiko/AP Photo)

Construction workers carry bricks on their heads near the country's parliament building in Naypyitaw November 11, 2014. Yangon lost its status as Myanmar's capital in 2005, after the former military junta carved a new seat of government from a parched wilderness some 380 km (236 miles) to the north and called it Naypyitaw (“Abode of Kings”). (Photo by Damir Sagolj/Reuters)

A worker carries a bag of salt after collecting it from a pond at the Maras mines in Cuzco December 3, 2014. Salt has been obtained in Maras since pre-Incan times by evaporating highly salty local subterranean stream water. The water is intricately channelled through constructions, flowing gradually down onto several hundred ancient terraced ponds. From each pond, a local member of the mine cooperative can produce 150 to 200 kilos per month which can be sold in the markets at $0.34 per kilogram, according to miners. (Photo by Enrique Castro-Mendivil/Reuters)