Gateshead Fell, site of medieval battle

The source for this reference is the following note by the 18th century antiquarian Brand: "In the year 1068, Northumberland was invaded, and the town now called Newcastle taken by Edgar Etheling, heir to the crown of England, together with Malcolm, King of Scotland, and some Danish pirates, whom William the Conqueror encountered in person, and overthrew on a heath adjoining to that place, and now called Gateshead Fell. Having recovered this place, King William is said to have laid it almost level with the ground, to prevent its becoming in future an asylum to his enemies".