The axes show that deep in the Ice Age, mammoth hunters roamed across land that is now submerged beneath the sea. These are the finest hand axes that experts are certain come from English waters, although there have been several finds on beaches, for example at Pakefield in Suffolk.

Phil Harding of Wessex Archaeology and Channel 4’s Time Team programme is an expert on the Ice Age. He said, 'These finds are massively important. In the Ice Age the cold conditions meant that water was locked up in the ice caps. The sea level was lower then, so in some places what is now the seabed was dry land. The hand-axes would have been used by hunters in butchering the carcasses of animals like mammoths.

'Although we don’t yet know their precise date, we can say that these hand axes are the single most important find of Ice Age material from below the North Sea.'

English Heritage, the Government’s advisory body for heritage, is cooperating with its Dutch counterparts, the National Service for Archaeology, Cultural Landscape and Built Heritage to evaluate the finds. The hand axes date to the Palaeolithic (or Old Stone Age) but exactly when in that 750,000 year time span is yet to be determined.

While the hand axes were discovered in Holland, the gravel came from a licensed marine dredging area in English waters known as Area 240, some 13km off Great Yarmouth lying in water depths of about 25m. Bones and teeth, some of which may be from mammoths, were also recovered along with the axes.

English Heritage is in the process of developing with the Dutch authorities a research programme for the submerged pre-history of the North Sea.

Ian Oxley, head of maritime archaeology at English Heritage said, 'These are exciting finds which help us gain a greater understanding of The North Sea at a time when it was land. We know people were living out there before Britain became an island, but sites actually proving this are rare.'

Ian Selby, Hanson’s marine operations and resources director added, 'The hand axes were collected over a three month period and this remarkable discovery only came to light in February when Mr Meulmeester, realising their importance, informed the wharf owners. As we manage our dredging very carefully, we were quickly able to identify the area where the finds came from. As part of our industry’s protocol with English Heritage, we have now moved dredging to another part of the seabed.'

The reporting of the hand axes demonstrates the level of cooperation that exists between the dredging industry, through its trade association, The British Marine Aggregate Producers Association (BMAPA), and English Heritage. The protocol, signed in 2005, aims to protect archaeological remains discovered in English waters as a result of marine sand and gravel extraction.

The reporting protocol for archaeological finds was an industry led initiative to prevent finds such as these going unreported. The potential for discovering finds has always been known to exist within dredging areas.  The industry with consultants Wessex Archaeology and English Heritage established a mechanism through which any finds could be reported and assessed. The guidance notes produced on behalf of English Heritage and BMAPA, can be viewed at: http://www.wessexarch.co.uk/projects/marine/bmapa/index.html