Mausoleum of Theodoric in Ravenna

The Mausoleum of Theodoric in Ravenna, Italy, was built in 520 A.D. with stones sourced from a quarry in Istria, approximately 400 km (249 miles) away by land. The mausoleum's roof consists of a single piece of Istrian carved stone 10 metres (33 feet) in diameter and weighing 230 tons.