In this photo taken Tuesday, October 14, 2014, skulls and bones are stacked at the Catacombs in Paris, France. The subterranean tunnels, stretching 2 kilometers (1.24 miles), cradle the bones of some 6 million Parisians from centuries past and once gave refuge to smugglers. The site used to close at 5 p.m., but is now staying open until 8 p.m. The change is mainly aimed at allowing more people to visit and reducing long lines, since it can only hold a limited number of people at a time and visits can't be reserved in advance. (Photo by Francois Mori/AP Photo)

Matador Marco Espinola, who emigrated from the Azores two years ago, challenges a bull during an Azorean “tourada a corda” (bullfight by rope) in Brampton, Ontario August 15, 2015. Bulls in a tourada a corda are held by a rope controlled by a team of men to make sure the animal does not cause injury. Bulls are never killed, in contrast with bullfighting in Spain. The Portuguese population in Canada, numbering 429,000 in the 2011 census, mainly centers around Toronto with immigrants from the nine islands of the mid-Atlantic Azores archipelago. (Photo by Chris Helgren/Reuters)

When Dutch photographer Marcel Heijnen moved to Hong Kong, the territory’s shop cats instantly caught his eye. While the “feline emperors” are the stars, his shots also offer insights into Hong Kong’s wares, from dried fish to paper. Here: Hong Kong Shop Cats #17. (Photo by Marcel Heijnen/Blue Lotus)

A gory fight to the death between snarling dogs and captured wild boars. Gathered around a bamboo-walled arena, Indonesians in this remote part of Java island seem eager to watch the blood-curdling contests, known locally as “adu bagong” (boar fighting). Not surprisingly, animal rights activists are up in arms against the regular spectacle, which began in the 1960s when wild pig numbers in this area in West Java soared and they were hunted to protect crops. Here: Women share a joke as they walk to a paddy field in Cikawao village of Majalaya, West Java province, Indonesia, October 12, 2017. (Photo by Reuters/Beawiharta)

(L-R) Edmea Pereira, 69, Elsa Rodrigues, 61, and Osmidio Conde, 71, take part in their surf class in Santos, Sao Paulo state, Brazil, March 16, 2016. When work is up, surf is up in Brazil, as a group of retired citizens take to the waves in keep-fit, keep-young sessions at a surf school in the city of Santos. The classes are run for free, three times a week at the Cisco Arana school, which aims to prove that age is just a number. (Photo by Nacho Doce/Reuters)

A debutante from a local academy looks at her mobile phone as she waits to take part in the Vienna Ball at the Kempinski Hotel, March 19, 2016, in Beijing. The ball, which is an event organized by the luxury Kempinski Hotel chain and the City of Vienna, brings together both Chinese and foreign members of the capital's elite class. Despite a slowing economy, private wealth has soared in China after decades of rapid growth. A record number of high net worth individuals and families has fuelled a market for luxury goods, services, and events catering to China's burgeoning elite class. (Photo by Kevin Frayer/Getty Images)

Auxiliary Territorial Service (ATS) plotters at work at Coastal Artillery Headquarters in Dover, December 1942. The Auxiliary Territorial Service was the women's branch of the British Army during the Second World War. It was formed on 9 September 1938, initially as a women's voluntary service, and existed until 1 February 1949, when it was merged into the Women's Royal Army Corps. The ATS had its roots in the Women's Auxiliary Army Corps (WAAC), which was formed in 1917 as a voluntary service. During the First World War its members served in a number of jobs including clerks, cooks, telephonists and waitresses. The WAAC was disbanded after four years in 1921. (Photo by Ted Dearberg/IWM/PA Wire)

Having $100 in your pocket would be so much cooler if it was designed by Martin Joubert. He went all out and created a number of different designs for the 100 USD banknotes, ranging from silly to witty. We especially liked the one with “That’s right. This is real money” written on it, showing just how many cups of coffee, basketballs, and guns you can buy with 100 dollars. All in all, even the currency that we have today is nothing but paper, even though it looks official and strict. There is nothing backing it up except for our noble military that ensures that Gulf States sell their oil using only the “green” kind of currency. (Photo by Martin Joubert)