Some of the world's best preserved prehistoric landscapes survive in pristine condition at the bottom of the North Sea, archaeologists claimed yesterday.

Academic interest in what are being described as drowned Stone Age hunting grounds is likely to increase dramatically after the discovery of 28 Neanderthal flint axes on the sea bed off the East Anglian coast.

Dating from at least 50,000-60,000 years ago, they were found with other flint artefacts, a large number of mammoth bones, teeth and tusk fragments, and pieces of deer antler. The sea bed location was probably a Neanderthal hunters' kill site or temporary camp site.