Secrets in the Ice

Visits to the most remote, cold and inhospitable places on the planet to reveal great mysteries that have been frozen in time. Here, a Swiss fisherman uncovers ancient Celtic relics in Lake Neuchâtel, hinting at a violent Iron Age battle that happened around 225BCE.

The Siberian death mask, which was discovered in eastern Siberia in 1968 in a burial mound with cremated remains. It is a clay head sculpture of a young man that contains a ram's skull.

Great mysteries that were once frozen in time, here focusing on secrets now revealed of prehistoric warfare.

The lost legacy of the Donner Party, a group of nearly 90 emigrants who left Illinois in the spring of 1846, heading westward to California in covered wagons. Delayed by a multitude of mishaps, they spent the next winter snowbound in the Sierra Nevada, with some resorting to cannibalism to survive.