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)

A Palestinian female masked militant from the Al-Quds Brigades, the military wing of the Islamic Jihad, takes part in an Islamic Jihad rally in Rafah, southern Gaza Strip, 29 July 2016. (Photo by Mohammed Saber/EPA)

An Afghan National Army (ANA) helicopter flies over a soldier during a training exercise at the Kabul Military Training Centre in Afghanistan October 7, 2015. (Photo by Ahmad Masood/Reuters)

A massive sand storm cloud is close to enveloping a military camp as it rolls over Al Asad, Iraq, April 27, 2005. (Photo by Cpl. Alicia M. Garcia, U.S. Marine Corps/Reuters/U.S. Department of Defense)

Seals dressed in military uniforms swim during a show marking the 70th anniversary of the end of World War Two, at an aquatic park in the Siberian city of Irkutsk, Russia, May 9, 2015. (Photo by Evgeny Kozyrev/Reuters)

Army soldiers prepare a military elephant for the parade during a rehearsal for Sri Lanka's 68th Independence day celebrations in Colombo, February 2, 2016. (Photo by Dinuka Liyanawatte/Reuters)

A military band playing during the Immortal Regiment march in Vladivostok, Russia on May 9, 2016. The celebrations marked the 71st anniversary of the defeat of Germany in WWII. (Photo by Yuri Smityuk/TASS/Getty Images)