Early borrowings like wine (Latin vinum), wall (Latin vallum), retain the w sound and are therefore spelt with w.
In later times the mound itself was frequently dispensed with, and the interments made within the enclosure of a trench, a vallum or a circle of standing stones.
Secondly, there is the so-called " Vallum," in reality no vallum at all, but a broad flat-bottomed ditch out of which the earth has been cast up on either side into g Bremen (Rochester) ijffabilasrciu.n