16th-century illustration, believed to show an auroch. Wikimedia Commons

A new TV documentary will this week reveal details of Adolf Hitler's secret plans to use Nazi experiments to bring seven feet beasts back from the dead – 350 years after they became extinct.

The documentary claims that Adolf Hitler and the Nazis planned to recreate aurochs, an ancestor of domestic cows, that stood seven feet tall with giant horns. The massive animals, which weighed more than a ton, once roamed the forests of Europe and are often depicted in ancient cave paintings in France and Spain.

An auroch cave painting in Lascaux, France Wikimedia Commons/Prof Saxx

Aurochs became extinct in the 17<sup>th century when the last known creatures died out in Poland. But Nazi experimenters planned to revive them, using an animal agricultural technique known as breeding back, to add a propaganda boost.

Breeding back is a process of selective breeding, whose ultimate aim is to create animals with predefined traits, even though the animal that the selective breeding produces may not be genetically related to the original.

The auroch experiments were masterminded by Hermann Goering, a key figure in the SS hierarchy and a keen hunter. Dr Toby Thacker, senior lecturer in modern European history at Cardiff University, told the Daily Mail: "For Goering, hunting was one of the greatest human activities and he believed there would be a special quality to these wild and ferocious animals. It was the ultimate hunting challenge."

The documentary – Hitler's Jurassic Monsters -- will air on National Geographic on Tuesday. But it is not the only attempt that scientists have made to recreate the mysterious aurochs.

In 2010 a Dutch preservationist group began a project to use breeding back to produce an animal that looks like an auroch. They say that if their attempts are successful the aurochs could return the European countryside to a more natural state, and may even eventually replace cows as domestic cattle.