The Devil's Dyke stretches in pretty much a straight line for more than seven miles through parts of Cambridgeshire and Suffolk. The best part, according to this scribbler anyway, is the section roughly a mile and half long which cleaves Newmarket's July Course from the Rowley Mile, with a break in the dyke allowing the two courses to join briefly just beyond the ten-furlong mark on the latter. A Dutch author, Iman Jacob Wilkens, once claimed that Cambridge's Gog Magog Hills was the true location of the City of Troy,...