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)

Željava Air Base, situated on the border between Croatia and Bosnia and Herzegovina under Plješevica Mountain, near the city of Bihać, Bosnia, was the largest underground airport and military air base in the former Yugoslavia, and one of the largest in Europe. (Photo by Thomas Windisch/Exclusivepix Media)

A model poses with a motorcycle and a car on a racing track at the Essen Motor Show in Essen, Germany, November 27, 2015. (Photo by Ina Fassbender/Reuters)

A person walks their dog in the morning mist at sunrise in Greenwich Park in south London on November 9, 2020. (Photo by Daniel Leal-Olivas/AFP Photo)

Models sit backstage during Dakar Fashion Week in the Senegalese capital, Friday June 30, 2017. The continent's fashion scene has grown steadily over the past two decades with Sub-Saharan Africa's apparel and footwear market now worth $31 billion, according to data by Euromonitor. (Photo by Finbarr O'Reilly/AP Photo)

U.S. singer Katy Perry slips on the icing of a giant cake that she had jumped onto as part of her performance at the MTV Latin America Awards in Guadalajara, in this October 16, 2008 file photo. (Photo by Daniel Aguilar/Reuters)

SpaceX’s Dragon spacecraft, March 6, 2014. SpaceX's Falcon 9 rocket and Dragon spacecraft launched from Launch Complex 40 at the Cape Canaveral Air Force Station, Florida, for their third official Commercial Resupply (CRS) mission to the orbiting lab on April 18, 2014. Dragon returned to Earth with a parachute-assisted splashdown off the coast of southern California on May 14, 2014. Dragon is the only operational spacecraft capable of returning a significant amount of supplies back to Earth, including experiments. (Photo by Ron Lin/SpaceX Photos)

Ryan Randall plays the bagpipes outside a polling station in Edinburgh, Scotland September 18, 2014. Polling in the referendum on Scottish independence began on Thursday morning, as Scotland votes whether or not to end the 307-year-old union with the rest of the United Kingdom. (Photo by Paul Hackett/Reuters)