Inmates sleep on the steps of a ladder inside the Quezon City jail at night in Manila in this picture taken on July 21, 2016. There are 3,800 inmates at the jail, which was built six decades ago to house 800, and they engage in a relentless contest for space. Men take turns to sleep on the cracked cement floor of an open-air basketball court, the steps of staircases, underneath beds and hammocks made out of old blankets. (Photo by Noel Celis/AFP Photo)

Tube passengers take a selfie next to a London underground roundel designed for the launching of the Night Tubes on display at Oxford Circus underground station in London, Britain, 19 August 2016. The long delayed Night Tubes service launched on 19 August. The 24-hour service will operate on Fridays and Saturdays. (Photo by Hannah Mckay/EPA)

An aerial view taken with a drone shows the autumnally colored Fuerst-Pueckler-Park near Cottbus, eastern Germany, Saturday, October 29, 2016. The park, composed with great sensitivity in the 19th century by Prince Hermann von Pueckler-Muskau, is considered as one of the last great German landscape gardens. (Photo by Patrick Pleul/DPA via AP Photo)

A Hindu devotee displays his inked hand after taking part in the religious festival of Holi in Vrindavan, in the northern state of Uttar Pradesh, India, March 8, 2017. (Photo by Cathal McNaughton/Reuters)

American students going wild during their Spring Break week-long recess in Cancun, Mexico on March 10, 2007. (Photo by Keystone USA/ZUMA Press/Rex Features/Shutterstock)

Replica of an old traditional Icelandic house from the 1800 with eruption of Iceland's Eyjafjallajökull volcano, 2013. (Photo by Ingólfur Bjargmundsson/Getty Images)

A visitor wears an outfit as she watches the St. George NextGen show for Fashion Week in Sydney on May 16, 2017. (Photo by Peter Parks/AFP Photo)

Laborers lay down upon a field to cut off the tulips that remained uncut by the tractor in Den Helder, Netherlands April 22, 2017. (Photo by Cris Toala Olivares/Reuters)