h2g2 The Hitchhiker's Guide to the Galaxy: Earth Edition

To help break the monotony of a journey on the M4 I can readily recomend the stretch of the A4 between Chippenham (J17) and Theale (J12). This is a lovely drive along the old London-Bristol road that takes in some wonderful countryside, a couple of white horses and two quaint little towns in Marlborough and Hungerford. The best part about this route is that the long sweeping stretches of the road remind you why you wanted to start driving in the first place. It is just a lot more fun and more interesting than the tedium of the M4.