Construction continues on One World Trade Center (TALLEST BUILDING AT LOWER LEFT) as the memorial footprints of the twin towers are seen (BOTTOM C) on August 12, 2011 in New York City. Upon completion, One World Trade Center will be New York's tallest skyscraper, topping out at a symbolic 1,776 feet, with 3 million square feet of office space. More than 2,700 people were killed when al-Qaeda terrorists hijacked U.S. passenger jets and flew them into the twin towers of the World Trade Center on September 11, 2001. Nearly ten years after the crippling attacks on Lower Manhattan, business, tourism and new construction like One World Trade Center have rejuvenated the formerly devastated cityscape.(Photo by Mario Tama/Getty Images)

A South Korean soldier wear North Korea's military uniform, acting as North Korean soldier during an anti-terror and anti-chemical drill session held as part of the 2011 Ulchi Freedom Guardian (UFG) event on August 17, 2011 in Seoul, South Korea. The 11-day UGC, which features drills including the handling of chemical and biological attacks, is a regular joint exercise between US and South Korean troops to prepare for potential emergencies on the Korean Peninsula. (Photo by Chung Sung-Jun/Getty Images)

A model presents a creation from Andres Sarda's Fall/Winter 2017 collection during the Mercedes-Benz Fashion Week in Madrid, Spain February 18, 2017. (Photo by Javier Barbancho/Reuters)

Extraordinary images of the cruise ship by Jonathan Danko Kielkowski from his book Concordia, published by White Press. The German photographer swam out to where the ship – which ran aground off Tuscany in 2012 with the loss of 32 lives – is moored. Francesco Schettino, the ship’s captain, was jailed for 16 years over the accident. (Photo by Jonathan Danko Kielkowski)

A police officer lies on the street after being run over by a bus during a protest against the increase in the price of public transport in San Cristobal, Venezuela March 29, 2016. (Photo by Carlos Eduardo Ramirez/Reuters)

Actors portraying "corrupted people" participate in the "Unmask the Corrupt" event, organized by the Transparency International non-governmental organization to create awareness on corruption, in Lima, November 12, 2015. (Photo by Mariana Bazo/Reuters)

A guard dog in the suburbs of Yakutsk, Russia, considered to be the coldest city in the world, January 2014. (Photo by Amos Chapple/REX Features)

The city of Meroë laid undiscovered for two millennia before British archaeologist John Garstang excavated it in the early 20th century. Garstang took the radical decision to document his discoveries with photography – and immortalised an ancient world. “Meroë: Africa’s Forgotten Empire” is being shown until 14 September at Garstang Museum of Archaeology, Liverpool. Here: A group visiting the excavations at Meroë, including (from left) Midwinter Bey, director of Sudan Railways; Lord Kitchener; General Sir Francis Reginald Wingate, Sirdar of the Egyptian Army; Professor Archibald Sayce; John Garstang; and Lady Catherine Wingate, 1911. (Photo by Garstang Museum of Archaeology)