Aerial dancers from Voloa, perform a dress rehearsal ahead of their performance at the opening night of Salisbury International Arts Festival on May 20, 2011 in Salisbury, England. The 39th Salisbury International Arts Festival runs from tonight until Saturday 4 June 2011 and features a programme of theatre, dance, circus, film, music, comedy and spoken word in locations around the historic city, from Salisbury Cathedral to Stonehenge. (Photo by Matt Cardy/Getty Images)

A two-horse team street cleaner, with sprayer, squeegee, and roller at rear. New York, between ca. 1910 and ca. 1915. (Photo by NYC Municipal Archives)

The classical ballet company “Ardentia” performs in the street of Mexico City on traffic lights, in an effort to highlight the city's fine arts in public spaces in Mexico, September 8, 2018. (Photo by Carlos Jasso/Reuters)

This photo taken on March 29, 2017 shows a young woman offering shots of liquer at a dance bar in Walking Street in Pattaya. Two hours east of Bangkok, Pattaya's bawdy reputation hails from the Vietnam War era when US GIs partied in their downtime. (Photo by Roberto Schmidt/AFP Photo)

Claire Robertson from Scottish Ballet, poses dressed as the Good Snow Flake inside a life size snow globe on Buchanan Street during a promotion for Scottish Ballet’s festive production of The Nutcracker on November 20, 2012 in Glasgow, Scotland. The Nutcracker opens at the Theatre Royal on December the 8th, the production delves deep into the darker reaches of Hoffmann’s original tale in a fresh and vivid retelling of the famous Christmas story. (Photo by Jeff J. Mitchell)

Pro-government fighters stand next to a tank destroyed during recent fighting in Yemen's southwestern city of Taiz March 14, 2016. (Photo by Anees Mahyoub/Reuters)