On 23 August 79 AD, Mount Vesuvius began to stir on the feast day of Vulcan, the Roman god of fire and volcanoes. The following day it erupted with extraordinary violence, burying Pompeii and Herculaneum and preserving them in volcanic ash for nearly two millennia. In 1973, a bank robbery in Stockholm gave rise to the term Stockholm Syndrome, describing the psychological phenomenon where hostages develop emotional bonds with their captors. In 1994, Eugene Bullard, the only African American combat pilot of the First World War who flew for France after being refused by the US Air Force, was posthumously commissioned as a Second Lieutenant, 33 years after his death. And in 1976, construction work near a Swiss reservoir revealed dinosaur footprints pressed into Alpine stone, dating back 240 million years to the early Triassic period. Four stories from the same date, each revealing something unexpected about human behaviour, geological time, and the strange coincidences history occasionally provides.