A reveller takes part in an annual block party known as “Ceu na Terra” (Heaven on Earth), one of the many carnival parties to take place in the neighbourhoods of Rio de Janeiro, January 30, 2016. (Photo by Pilar Olivares/Reuters)

A reveller (R), dressed as “Diablos de Luzon” (Luzon Devils), stands next to a person dressed as a “Mascaritas” during carnival celebrations in the village of Luzon, Spain, February 6, 2016. The “Diablos” cover themselves in a mixture of soot and oil and adorn their heads with black-stained bull horns as they parade throughout the village with cowbells clanging around their waists to expel the evil spirits. (Photo by Sergio Perez/Reuters)

A woman sits on a terrace at Tiki hostel in Cantagalo favela, in Rio de Janeiro, Brazil, April 16, 2016. Hostels in a few of Rio's more than 1,000 slums serve not only as a cheap housing alternative for the more adventurous among the estimated 500,000 foreign tourists expected to arrive for the Olympics in August. The establishments also open up the rich culture of the city's shantytowns for travellers, giving them a glimpse into once “no-go” areas where about one-fifth of Rio's population lives. (Photo by Pilar Olivares/Reuters)

A reveller wearing a demon costume takes part in the traditional festival of “Correfoc” in Palma de Mallorca, on January 17, 2015. The Correfoc is a night of revelry in which participants dress as demons and devils, and move through the streets scaring people with fire and fireworks. (Photo by Jaime Reina/AFP Photo)

Model Bella Hadid attends the “Cafe Society” premiere and the Opening Night Gala during the 69th annual Cannes Film Festival at the Palais des Festivals on May 11, 2016 in Cannes, France. (Photo by Tristan Fewings/Getty Images)

A girl looks at other children practicing on a boxing ring during an exercise session at a boxing school, in the Mare favela of Rio de Janeiro, Brazil, June 2, 2016. For many young residents the Luta Pela Paz (Fight For Peace) academy offers a glimpse of an alternative: a chance to build discipline and self-esteem through boxing and martial arts. (Photo by Nacho Doce/Reuters)

Brazil's synchronised swimmers Luisa Borges (front) and Maria Eduarda Miccuci perform during a training session at the Rio Olympic Park in Rio de Janeiro, Brazil, April 7, 2016. (Photo by Pilar Olivares/Reuters)

The Eiffel Tour-the body language of balance. I came across this group of young adults from Sarajevo, Bosnia, having fun testing their balance two nights ago in on the Esplanade de Trocadero. (Photo and comment by Peter Turnley)