A mass pillow fight in Trafalgar Square in central London on April 5, 2014 on International Pillow Fight Day. (Photo by Jane Scanlan)

“If a man insisted always on being serious, and never allowed himself a bit of fun and relaxation, he would go mad or become unstable without knowing it”. – Herodotus. “You can discover more about a person in an hour of play than in a year of conversation”. – Plato. Photo: Mandalay, Burma. (Photo by Steve McCurry)

“Rivers Forgotten” is a journey through the passages and portals of the underground waterways that lie unseen below cities. Self-taught photographer Jeremy Kai brings these forgotten landscapes to light. Photo: Beneath the Toronto area, 2011. (Photo by Jeremy Kai)

In addition to the publication of «146 West End Stars Hold A Flashmob In Trafalgar Square». Good people have sent us exclusive photos of the event (and to prepare for it). Many thanks to Christopher Voodhams, and the author of these wonderful photos – photographer Eduardo Carrasco! (Photos by medialabs.net).

The annual Antarctic photography exhibition, which is part of Hobart’s Antarctica festival is back on with its chilly, majestic imagery. The winner this year is Sydney’s Sam Edmonds with his striking photo of a gentoo penguin in the snow. Here: Casey Station 2017. (Photo by Chris J. Wilson/The Guardian)

Russian pop art photographer Sergey Chilikov captures a nation liberated from the social oppression of late-era Soviet rule – at parties, in the streets, and bouncing high. His exhibition, Photoprovocations, will be at Photo London, 19-22 May. Here: Yoshkar-Ola, Matrosova Street (1995). (Photo by Sergey Chilikov)

A woman is tattooed by an artist during Warsaw Tattoo Convention 2014 in Warsaw November 29, 2014. (Photo by Kacper Pempel/Reuters)

A Brazil fan enjoys the atmosphere prior to the 2014 FIFA World Cup Brazil Semi Final match between Brazil and Germany at Estadio Mineirao in Belo Horizonte, Brazil, on Jule 8, 2014. (Photo by Robert Cianflone/Getty Images)