A group of people are seen on a Victoria line train in London, England during the first night of the Night Tube service on August 19 2016. The Central line and Victoria line are the first to operate a Night service with further lines expected to be running by the end of the year. (Photo by SWNS.com)

A Syrian refugee girl covers herself with a blanket as she stands outside tents at a makeshift settlement in Bar Elias in the Bekaa valley January 5, 2015. Lebanon enforced new immigration controls at the Syrian border on Monday in a move to gain control of the steady stream of refugees from its much larger neighbour. (Photo by Mohamed Azakir/Reuters)

Fort Bourtange is a star fort located in the village of Bourtange, Groningen, Netherlands. It was built in 1593 under the orders of William the Silent. Its original purpose was to control the only road between Germany and the city of Groningen, which was controlled by the Spaniards during the time of the Eighty Years' War.

Boys play with a drainage culvert used for flood control in Las Pinas, Metro Manila February 28, 2016. (Photo by Erik De Castro/Reuters)

A clothing shop displays its merchandise in the rebel-controlled city of Idlib, Syria November 7, 2015. (Photo by Ammar Abdullah/Reuters)

Damaged buildings stand in the rebel-controlled area of Maaret al-Numan in Idlib province, Syria September 6, 2016. (Photo by Ammar Abdullah/Reuters)

Women pose for a picture at the entrance of the Carlton Hotel, in the government controlled area of Aleppo, Syria December 17, 2016. (Photo by Omar Sanadiki/Reuters)