During the Second World War, a small, uninhabited island off Scotland’s north-west coast became the site of one of Britain’s most secret military experiments. In 1942, Gruinard Island was deliberately contaminated with anthrax spores as part of a classified biological warfare programme designed to test whether the deadly bacterium could be used against enemy livestock….

Image: National Geographic In March 1999, archaeologists climbing one of the highest volcanoes in the Andes discovered something never seen before. Near the 6,739-metre summit of Mount Llullaillaco, on the border of Argentina and Chile, they uncovered the remarkably preserved body of a teenage Inca girl who had remained frozen for more than 500 years….

For years, China’s empty subway stations became some of the internet’s favourite examples of “ghost cities” and questionable urban planning. Images of polished platforms, escalators and station entrances surrounded by fields appeared to show infrastructure built far ahead of demand. Among the most famous examples was Caojiawan Station in Chongqing, which seemed to stand alone…