古代の Offa's Dyke between England and むちの跡s may be 改名するd after 専門家s discover it was built 200 years before King Offa was born

• Archaeologists used radiocarbon dating on the 177-mile dyke
• Thought to have been built by King Offa of Mercia in the 8th century
• 専門家s Discovered it could have been 建設するd in the 4th century
  
• Runs from Prestatyn in North むちの跡s 負かす／撃墜する to Chepstow in the south
  
• King Offa （機の）カム to the 王位 in 757 and 支配するd until 796?
  

By Wills Robinson

Published: 17:55 BST, 8 April 2014 | Updated: 19:29 BST, 8 April 2014

It was thought to have built by King Offa in the 8th century as 国境 between England and むちの跡s

But even though it has been part of the British landscape for centuries, the 古代の Offa's Dyke may have to be 改名するd, after archaeologists discovered it could have been 完全にするd 200 years before the 広大な／多数の／重要な Anglo Saxon leader was born.

専門家s used radiocarbon dating on the 177-mile dyke and 明らかにする／漏らすd it could have been 建設するd as 早期に as the 4th century.

古代の: Archaeologists have used radiocarbon dating on the dyke, which 行為／法令／行動するd as a 障壁 between England and むちの跡s. Results 明らかにする／漏らすd it had been 建設するd at least 200 years earlier than first thought

It was 任命する／導入するd to 保護する the Kingdom of Mercia, which is now known as the Midlands, from an 侵略 by Welsh 軍隊s.

The group behind the 事業／計画（する） said it is a 'tremendously exciting 発見' which challenges the 受託するd history of the 古代の dyke.

The Clwyd-Powys Archaeological 信用 穴掘りs were carried out on a stretch of the dyke along the Shrop shire 国境 近づく the town of Chirk.

Paul Belford, director of the? Archaeological 信用, said: 'It's been known as Offa's Dyke for centuries but some sections may not have been built by Offa.

'It may be a bit late to change the 指名する now - although it raises some 利益／興味ing questions.'

The dyke, an Anglo-Saxon earthwork up to 65ft wide in places, was built as a man-made 国境 between England and むちの跡s.

It was built by Offa of Mercia, who （機の）カム to the 王位 in 757 after the 殺人 of his cousin Ethelbald.

He 支配するd the area now know as the Midlands and historians say he was the most powerful Saxon 支配者 before Alfred the 広大な／多数の／重要な.

Today it is a 保護するd monument and The Offa's Dyke Path is one of Britain's longest walks - stretching rom Prestatyn in North むちの跡s 負かす／撃墜する to Chepstow in the South.

Change: 専門家s believe the 177-mile Offas's Dyke, which runs from Prestatyn in North むちの跡s to Chepstow, may have to be re-指名するd because of the 発覚

君主: A 製図／抽選 of King Offa who 統治するd from AD 757 to 796 and was regarded as the most powerful Anglo Saxon leader before Alfred the 広大な／多数の／重要な

The 構成要素 （機の）カム from an 古代の 層 of re-deposited turf underneath the bank 示唆するing it was laid 負かす／撃墜する as part of the construction 過程.

Mr Belford said: 'This is the first time we have 正確な 科学の dates for Offa's Dyke.

'Certainly the dyke was built to make a 声明 about the 力／強力にする of the kingdom of Mercia.'

Until now historians believed the dyke was built by King Offa of Mercia during his 統治する between 757 and 796.

Natural beauty: The structure is a 保護するd monument and is now one of Britain's longest walks

But the section of earthwork 近づく Chirk have been 炭素 時代遅れの and 明らかにする／漏らすd a 95 per cent probability it was built between 430 and 652.

Mr Belford said: 'It is likely that parts of the dyke system was in place before Offa's time.

'But it is also likely that he would have 強固にする／合併する／制圧するd the 存在するing 網状組織 into what we now call Offa's Dyke.

'It is now （疑いを）晴らす that it was not the work of a 選び出す／独身 支配者 but a longer-称する，呼ぶ／期間／用語 事業／計画（する） that began at an earlier 行う／開催する／段階 in the 開発 of the kingdom.

'その上の work is needed on other parts of this enigmatic monument before we can really say who built it and why.'

発覚s: Archaologists said the new date was a 'tremendously exciting 発見' which challenges the 受託するd history of the 古代の dyke

調査: However, the group said more work needed to be done before any その上の 活動／戦闘 was taken

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