Offa's Dyke may be misnamed

Offa's Dyke, a linear earthwork stretching 177 miles (285 km) in Chirk near the Shropshire border, may be misnamed. Legendarily built by King Offa of Mercia during his reign between 757 and 796, the earthwork may actually be 200 years older.

Carbon dating of the Chirk section of the dyke place its construction between 430 and 652. "This is a tremendously exciting discovery which means we must re-think some of our assumptions about this important monument", said Paul Belford, the director of the Clwyd-Powys Archaeological Trust, wich undertook the study.