Across two very different continents, scientists are mapping vast systems of ancient tunnels that were not carved by rivers ...

Looks like limestone’s on the menu for some unknown microbe.

Add Yahoo as a preferred source to see more of our stories on Google. An underground tunnel network long rumored thanks to drawings by Leonardo da Vinci under Milan’s Sforza Castle is now proven to ...

A top travel destination has uncovered an ancient secret. A little-known network of subterranean passageways hidden beneath Rome’s Capitoline Hill — holding clues to a long-ago chapter of the Eternal ...

To find catacombs, go to Rome, home of some of the oldest and longest burial underground tunnels in the world. "Hundreds of kilometers of catacombs run underneath the town and its outskirts," says ...

During renovation of a street in Split, Croatia, archaeologists revealed an ancient Roman tunnel leading to cellars of Diocletian’s Palace. Photo from Vesna Bulić Baketić As workers dug up a street in ...

JERUSALEM — Under threat from Romans ransacking Jerusalem 2,000 years ago, many of the city's Jewish residents crowded into an underground drainage channel to hide and later flee the chaos unnoticed ...

Mysterious micro-burrows in desert marble and limestone were probably made by microbes that lived millions of years ago. Exactly what kind of microbes bored into the rock remains unknown, as does ...