Researchers in Kent have unearthed some of the largest early prehistoric stone tools ever found in Britain. Excavations revealed artifacts in deep Ice Age sediments preserved on a hillside above the Medway Valley. A total of 800 artifacts, thought to be more than 300,000 years old and buried in material that filled a sinkhole and ancient river channel were discovered. Senior archaeologist Letty Ingrey said the discovery included a footlong hand axe almost too big to be handled. Ms Ingrey, of UCL Institute of Archaeology, said: "We describe these tools as giants when they are over 22cm long, and we have two in this size range. "The biggest, a colossal 29.5cm in length, is one of the longest ever found in Britain. "These hand axes are so big it"s difficult to imagine how they could have been easily held and used." She speculated that the tools might have fulfilled a less practical or more symbolic function. "Right now, we aren"t sure why such large tools were being made, or which species of early human were making them," she added. "This site offers a chance to answer these exciting questions." The excavation site is thought to date to a period in the early prehistory of Britain when Neanderthal people and their cultures were beginning to emerge and may even have shared the landscape with other early human species. At this time, the Medway Valley would have been a wild landscape of wooded hills and river valleys, the researchers said. It would have been inhabited by red deer and horses, as well as less familiar mammals, such as the now-extinct straight-tusked elephant and lion. Dr Matt Pope, of UCL Institute of Archaeology, said: "The excavations at the Maritime Academy have given us an incredibly valuable opportunity to study how an entire Ice Age landscape developed over a quarter of a million years ago." The team also made a second significant find at the site - a Roman cemetery, dating to at least a quarter of a million years later than the Ice Age activity. — BBC