QATAR-TREK-DESERT

Sheikh Mubarak bin Salah bin Kla, 30, rides his camel on January 26, 2016 in the desert, south of the Qatari capital Doha, before the start of the last leg of a 50-day trek across the world's largest sand desert that will end in Doha. A team of intrepid walkers and their camels are on the verge of successfully retracing the historic 1,300-kilometre (800-mile) route taken in 1930 by British civil servant and Arabist Bertram Thomas. The three-man team walked from Salalah in southern Oman, through Saudi Arabia, to Doha, across a vast stretch of uninhabited land in the southern Arabian peninsula known as the Empty Quarter. / AFP / OLYA MORVAN / TO GO WITH AFP STORY BY DAVID HARDING (Photo credit should read OLYA MORVAN/AFP via Getty Images)