Pedestrians cover their face as they walk along the dusty road in Kathmandu, Nepal February 27, 2017. Nepal has forced 2,500 old vehicles off roads in its capital city of Kathmandu, part of a fight against alarming air pollution levels that have hit nine times World Health Organisation (WHO) limits. Air pollution has been a chronic problem in rapidly growing Kathmandu, which sits in a Himalayan valley and is home to more than 3mn people. (Photo by Navesh Chitrakar/Reuters)

Pedestrians and workers pass an upside down car art installation in a car park on the South Bank in London, February 19, 2015. British artist Alex Chinneck's illusory piece, entitled “Pick yourself up and pull yourself together”, and on display in the working car park for a week, sees a Vauxhall car suspended upside down, appearing to be gripping onto a peeled back length of tarmac. (Photo by Toby Melville/Reuters)

The knitted sculpture “William Tell” by Patricia Waller sits in the “Broken Heroes” exhibition at the Deschler Gallery on April 26, 2012 in Berlin, Germany. The exhibition of hand-crocheted comic, puppet and cartoon figures shows icons of pop culture in various unfortunate states. (Photo by Adam Berry)

Stefan Libon proposes to girlfirend Jess McGarrity in front of a banner message “Marry Me Jess?” on the deck of the Queen Mary 2, at Mrs Macquarie's Chair on Valentines day, February 14, 2012 in Sydney, Australia. (Photo by James Morgan/Carnival Australia via Getty Images)

Venezuelan tattoo artist and body modifier Emilio Gonzalez (L) takes a picture of the eyeball tattoo on Eduardo Henriquez, 19, of Chile during the latin america convention of tattoo and suspension in Valparaiso city November 8, 2015. (Photo by Rodrigo Garrido/Reuters)

A deserted alley in the ghost town of Apice, in the province of Benevento, southern Italy, 22 November 2016. After the Irpinia earthquake that took place in southern Italy on 23 November 1980, leaving at least 2,500 people dead, 8,000 injured and 250,000 homeless, the town in the heart of the Sannio area was evacuated and its residents moved into what has become the new Apice. Only recently the narrow streets and the tragically abandoned buildings have started, slowly, to repopulate. (Photo by Cesare Abbate/EPA)

An mechanic in Brick Lane Bikes repairs a fixed wheel bike in their shop in Shoreditch on June 14, 2011 in London, England. The UK bike industry has seen a dramatic rise in the number of people building their own custom bikes or purchasing bespoke bikes. (Photo by Oli Scarff/Getty Images)

The wreckage of a van is overgrown by plants in Simacem village in North Sumatra, Indonesia, November 16, 2015. The village was abandoned following the eruption of Mount Sinabung as it was considered too close to the still rumbling volcano. (Photo by Binsar Bakkara/AP Photo)