Editing Offa's Dyke (section)

===Early scholarship===
[[File:Offa's Dyke near Yew Tree Farm - geograph.org.uk - 450420.jpg|thumb|Offa's Dyke near [[Presteigne]], Powys]]
The first historians and archaeologists to examine the dyke compared their conclusions with the late 9th-century writer [[Asser]], who wrote: "there was in Mercia in fairly recent time a certain vigorous king called Offa, who terrified all the neighbouring kings and provinces around him, and who had a great dyke built between Wales and Mercia from sea to sea".<ref>Asser, ''Life of Alfred'', p. 14</ref> In 1955, [[Cyril Fox]] published the first major survey of the dyke.<ref>Fox 1955</ref> He concurred with Asser that the earthwork ran 'from sea to sea', theorising that the dyke ran from the [[River Dee, Wales|River Dee]] estuary in the north to the [[River Wye]] in the south: approximately {{convert|150|mi}}. Although Fox observed that Offa's Dyke was not a continuous linear structure, he concluded that earthworks were raised in only those areas where natural barriers did not already exist.

Historian [[Frank Stenton]] accepts Fox's conclusions. He wrote the introduction to Fox's account of the dyke. Although Fox's work has now been revised to some extent, it still remains a vital record of some stretches of Offa's Dyke that still existed between 1926 and 1928, when his three field surveys took place, but have since been destroyed.