The ancient city of Herculaneum, Italy, buried by the eruption of Mt. Vesuvius in 79 AD

Click on above photo to view it in large format: Standing above the excavation site at the ruins of Herculaneum, Italy. The town was completely buried by successive, rapid flows of pyroclastic volcanic mud from the eruption of Mount Vesuvius in 79 AD. As a result, the entire city was perfectly preserved in the encased mud, right down to frescoes on the walls. Note the modern day homes on the top of the ridge; the burial of the city was so complete that it was built over and not discovered again until the mid-18th century.