A reveller catches beer thrown from a balcony during the opening day or “Chupinazo” of the San Fermin Running of the Bulls fiesta on July 6, 2017 in Pamplona, Spain. The annual Fiesta de San Fermin, made famous by the 1926 novel of US writer Ernest Hemmingway entitled “The Sun Also Rises”, involves the daily running of the bulls through the historic heart of Pamplona to the bull ring. (Photo by Pablo Blazquez Dominguez/Getty Images)

Participants hold red scarves as they celebrate the “Chupinazo” marking the start at noon sharp of the San Fermin Festival at Castle square in Pamplona, northern Spain on July 6, 2013. Ten of thousands of people packed Pamplona's streets for a drunken kick-off to Spain's best-known fiesta: the nine-day San Fermin bull-running festival. (Photo by Pedro Armestre/AFP Photo)

Revellers celebrate moments before the rocket fire or “Txupinazo” marks the start of the Festival of San Fermin (or Sanfermines) at Consistorio square in Pamplona, Spain, 06 July 2014. The annual nine day long running-with-the-bulls fiesta commemorates St. Fermin, Pamplona's patron saint. (Photo by Javier Lizin/EFE)

Jason Garcia poses as The Joker from Batman at the 2015 Comic-Con International in San Diego, California, July 9, 2015. (Photo by Sandy Huffaker/Reuters)

A man with a mask poses for a portrait as he takes part in festivities in honour of patron saint San Jeronimo in Masaya city, Nicaragua November 20, 2016. (Photo by Oswaldo Rivas/Reuters)

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)

A pet owner holds his guinea pig named Riec as Father Francisco bestows a blessing on the pet rodent during a feast day Mass in honor of Saint Anthony, the patron saint of animals, at the Saint Fernando church, in Mexico City, Saturday, January 17, 2015. Many people in Mexico bring their pets to churches to be blessed by the priest on this day. (Photo by Marco Ugarte/AP Photo)