PEMBROKE — The University of Aberdeen will launch a five-year archaeological project at Wogan Cavern, a prehistoric cave beneath Pembroke Castle in Wales, with larger-scale excavations due to resume in May. The cave, accessed via a spiral staircase from the 11th Century castle, has already yielded hippo bones and evidence of early human occupation.

Previous small-scale excavations at the castle uncovered stone tools and bones of mammoth, woolly rhinoceros, reindeer and wild horse, along with the remains of a now extinct hippopotamus that roamed Wales about 120,000 years ago.

The project will be led by Rob Dinnis, who said the site stood apart from others in the region. "There is no other site like it in Britain -- it is a once-in-a-lifetime discovery," he said. Despite limited work conducted so far, Dinnis said the initial findings were already unusual. "Despite the limited work done so far, we can already say that Wogan Cavern is a truly remarkable site."

Professor Kate Britton said the condition of the material at the site would allow researchers to apply a full range of modern methods. "Wogan Cavern provides a unique chance to use all the scientific techniques now available to archaeologists," Britton said. She added that the preservation of the remains opened a window onto ancient environments. "Because the bones are well preserved, we can learn a lot about past environments and ecosystems."

Castle manager Jon Williams welcomed the continuation of research at the site. "This is incredibly exciting news for everyone at the castle," Williams said. "We are thrilled that work on this wonderful cave will continue."