The roundel structure uncovered in the outskirts of Prague, Czech Republic. It's thought to have been built around 7,000 years ago.

The excavated roundel is large — about 180 feet (55 meters) in diameter, or about as long as the Leaning Tower of Pisa is tall, Radio Prague International reported. And while "it is too early to ...

A mysterious, newly discovered stone roundel in Prague is older than Stonehenge and the Egyptian pyramids, built some 7,000 years ago during the Stone Age. Its purpose remains unknown.

This particular roundel was first discovered in the 1980s, but new radiocarbon tests reveal that the Neolithic structure dates back to the years between 4900 B.C. and 4400 B.C and once had three ...