The Roman road system of Kent did the same thing over the Wansum when that stream was--as Rice Holmes has proved--a broad estuary 3000 yards across, with Richborough as an island in its midst. The Roman road from Dover and the one from Canterbury met at a point opposite Richborough, whence a ferry took people across to Richborough. Again, the Roman road to the lead mines of the Mendips ends at the wide mouth of the Severn, and is carried on again on the far Welsh side. But every road system since has gone right round by Gloucester, and the inconvenient effects of this, as road travel develops and water carriage declines, are very noticeable to-day. In all that southern coast of Devon between Lyme Regis and the Exe, if you want to get round to the maritime south-western bulge of the county you must make an elbow through Exeter. Similarly the Sussex coast, now so crowded, has only been linked up quite recently by bridges: the one at Shoreham was built within living memory, the swing bridge at Littlehampton is an affair of the last few years, as also the swing bridge at Newhaven of this generation. For 1500 years no one could proceed along that coast continuously from, say, Portsmouth by Littlehampton, Shoreham, Seaford (later Newhaven), Hastings, Rye, without turning inland to cross at Arundel, at Bramber, at Lewes, at Robertsbridge. One of the subsidiary effects of this interruption was the comparative ease with which the coast could be attacked from the sea, for the difficulty of rapid concentration upon any one point, in the lack of lateral communication, handicapped the defending force by land. All through mediaeval history the Sussex coast was raided from the sea. So much for the effect of waterways, the main physical cause of diversion in the English Road. iii The political cause of diversion has been, as I say, the negative effect of an absence of grand strategy in modern times. There has been no grand strategy in this country since the Romans, because there has been no fighting of a highly-organized type within the island during the whole of its post-Roman history. There was a great deal of barbaric fighting in the Dark Ages, and a great deal of feudal fighting in the Middle Ages. Even in the beginning of modern organized warfare you had (on a very small scale, it is true) the civil wars. But since then--that is, during the whole of the period in which modern road systems have developed (1660 onwards)--there has been no necessity for strategical considerations to affect the English road system at all, and, therefore, no political force strong enough to compel direct roads was present in opposition to the strong economic motive for diversion.