"In AD 757 the dark-age Saxon, Offa, became king of Mercia, a region that is roughly equivalent to the English Midlands today.

This was not, however, to become just another footnote in history, because Offa was to do something remarkable that would help to influence the geography, language and culture of what would eventually become the countries of Wales and England.

He constructed the great linear earthwork that we know today as Offa's Dyke, a rampart and ditch, and in so doing effectively defined Wales.

Today in places it still forms the national boundary, in fact the long-distance footpath, Offa's Dyke Path National Trail, crosses the Dyke a total of 27 times, indeed the walker can forgiven for wondering at times just what country they are in.

But then for most there is the realisation that it really doesn't matter because this border has an identity and character of its own, a mixture of Welsh and English, the Welsh place names that survive well into England attest to that.

The Dyke remains something of an enigma, archaeologists and historians are still debating whether Offa intended it as a border or a military frontier, but for its visitors this only adds to its lure.

The 1250th anniversary of Offa's accession is also worth considering for those living east of the Scheduled Ancient Monument because Offa almost, but not quite, formed a united England - but that would have to wait until later.

He not only reformed the coinage (we still use the penny) but also had links with Charlemagne and established international trade as far afield as the middle east.

The Saxon word for boundary, Merc, has also given us the modern name for the border landscape, the Welsh Marches.

The best way of exploring the Dyke is to walk some or all of the National Trail.

Some 175 miles long you can dip in and out of it as your time permits.

For advice on visiting the Dyke and Trail contact the Offa's Dyke Centre in Knighton. Telephone: 01547 528753."

Article written by David McGlade