If it is difficult to offer any convincing argument as to the age of the wall of London, it is possible to get a general idea of the walled city and its neighbourhood with some vividness and accuracy. We have the great tidal river, the background of forest, and the nearer fen-lands, which seem to have almost insulated the site. There is the great white posting-road from Canterbury and Dover, and, more remotely, from Rome, Lyons, Chalons, Auxerre, Troyes, Rheims, Amiens, Boulogne, striking straight from point to point. On its course are villas, like one just discovered in Greenwich Park. The road dips towards the river, and passes over the drained and banked marshes to the Surrey suburb. There is a gate-tower at the end of the Bridge, then comes the long and narrow passage over the strong, swift river to the grey walls of Londinium. Along the river-front are several wharves formed of timbering, to the left is the creek of the little river which ran under the west walls, and, still further west, some water-side villas.[215] Entering the city the street ascends steeply towards the north gate; others, parallel to its course, lead to two other gates in the north wall, and two chief routes traverse the city longitudinally from west gate to east gate, and from west postern to east postern. A bridge[216] over the Walbrook gives good reason why the street lines in the eastern half of the city converge toward this point. The area extending from the north-gate street to the bank of the Walbrook is covered with the principal buildings closely packed together.[217] Beyond this central mass of buildings stand isolated villas in gardens and orchards. In the open belt of ground outside the walls, and along the roads, west, north, and east, are cemeteries, the graves marked with sarcophagi and sculptured headstones, some of imported marble. A theatre somewhat similar to those at Dorchester, Cirencester, and Silchester is situated without the west gate, being excavated in the steep bank of the rivulet between it and the city wall.[218] [Illustration: FIG. 38.--ROMAN TOMB, FROM OUTSIDE OF THE EAST WALLS. RESTORED.] [Illustration: FIG. 39.--INSCRIPTION FROM ROMAN TOMB.]