When Caesar, eager for spoil and conquest, marched across country from Deal, and first saw the Sarn Gwyddelin from the summit of Barham Downs, it could have been but a track, never _built_, but gradually brought into existence by the tramping of students and fighting-men, and widened by the commerce of those exclusive merchants. Thus it remained for _at least_ ninety-eight years longer; rough, full of holes, mires, and swamps, and crossed by many streams. Caesar came and went; and not until Aulus Plautius and Claudius had overrun Britain, and probably not before many successive Roman governors had served here, and reduced this province of Britannia Prima to the condition of a settled and prosperous colony, was the Foreigners' Road made a _via strata_, a paved Roman Military Way. Its date might be anything from the landing of Aulus Plautius, in A.D. 45, to the time of Hadrian, the greatest of all road-builders, A.D. 120. Then it became a true "street," made in the thorough manner described by Vitruvius, and paved throughout with stone blocks; the "_strata_" from which the word "street" is derived. Engineered with all that road-making science which, not less than their victories, has rendered the Romans famous for all time, the Watling Street, as the Romans left it, stretched from sea to sea. Starting from their three great harbour fortresses on the Kentish coast--from _Rutupiae_, _Portus dubris_, and _Lemanis_, Englished now as Richborough, Dover, and Lympne--it converged in three branches upon their first inland camp and city of _Durovernum_, where Canterbury now stands. Proceeding thenceforward on the lines of the present Dover Road, the Roman road came to their next station of _Durolevum_, whose site no antiquary has fixed convincingly, but which might have been at either Sittingbourne, Ospringe, Davington, or Key Street. Thence it reached _Durobrivae_, which was certainly on the site of Rochester. Crossing the Medway by a _trajectus_, or perhaps even by a bridge of either stone or wood, the road passed through Strood, and branched off through Cobham, coming again to the modern highway at Dartford Brent. Perhaps it even had two branches here, one touching the river at _Vagniacae_, probably both Northfleet and Southfleet; and the other keeping, as we have seen, inland until a junction was effected near Dartford. But with its proximity to London, the story and the geography of Watling Street grow not a little confused. Where, for instance, the succeeding station of _Noviomagus_ was situated no one can say with certainty. It might have been at Keston; it probably was at Crayford; or there _might_ have been two branches again, as some antiquaries suggest. Through London, the Watling Street went across England, past St. Albans and Wroxeter, and finally to _Segontium_, or the hither side of the Menai Straits, throwing off a branch to _Deva_, Chester.