Watt's Dyke
Watt's Dyke:
see Offa's DykeOffa's Dyke,ancient entrenchment of W England and E Wales, from the Dee estuary to near the estuary of the Wye River. It was built in the 8th cent. by Offa, king of Mercia, as a barrier against the Welsh and lies mainly along the England-Wales boundary.
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