In 2008, workmen digging trenches for electrical cables in the Estonian island town of Salme uncovered human bones and a variety of objects that they piled next to their trench. At first the bones were thought to be from a soldier killed in World War II, but archaeologists realized that the objects dated to the Viking period. A small team of archaeologists working under Marge Konsa, an archaeologist at the University of Tartu, started excavating and soon found the hull of a ship. Nearly all of the ship's timber had rotted away, leaving behind only discolorations in the soil. But...