A remarkable discovery has been made by archaeologists beneath the Baltic Sea - a 3,000-foot-long stone wall that could revolutionize our understanding of Europe's prehistoric past. The structure ...

researchers at ETH Zurich have let an autonomous excavator loose on a big pile of boulders and reclaimed concrete. The goal? To build a 20 foot (6 meter) and 213 ft (65 m) long dry-stone wall as ...