Hypogeum of Hal-Saflieni in Malta

de bene esse: literally, of well-being, morally acceptable but subject to future validation or exception

On the island of Malta is a prehistoric underground megalithic structure known as the Hypogeum of Hal-Saflieni, which sounds like the title of Terry Gilliam's next movie. It was discovered by accident in 1902 while workers were digging a hole and broke through the ceiling. They also found about 7,000 skeletons all clustered near the entrance. Creepy.

Since most humans inherently lack common sense, the workers decided to take a look around, instead of fleeing from whatever it was that 7,000 people clearly died trying to escape. Luckily, rather than having their faces melted off by an Indiana Jones MacGuffin, they found something truly astonishing.