C. 8.--On most of these sites continuous occupation for many subsequent ages has blotted out the vestiges of their Roman day. Every town has a tendency literally to bury its past; and the larger the town the deeper the burial. Thus at London the Roman pavements, etc. found are some twenty feet below the present surface, at Lincoln some six or seven, and so forth. To learn how a Roman town was actually laid out we must have recourse to those places which for some reason have not been resettled since their destruction at the Anglo-Saxon conquest, such as Wroxeter and Silchester, where the remains accordingly lie only a foot or two below the ground. The former has been little explored, but the latter has for the last ten years been systematically excavated under the auspices of the Society of Antiquaries, the portions unearthed being reburied year by year, after careful examination and record.[224] C. 9.--The greater part of the site has thus been already (1903) dealt with; proving the town to have been laid out on a regular plan, with straight streets dividing it, like an American city, into rectangular blocks. Twenty-eight of these have, so far, been excavated. They are from 100 to 150 yards in length and breadth, arranged, like the blocks in a modern town, with houses all round, and a central space for gardens, back-yards, etc. The remains found (including coins from Caligula to Arcadius) prove that the site was occupied during the whole of the Roman period. Originally it was, in all probability, one of the towns built for the Britons by Agricola[225] on the distinctive Roman pattern, with a central forum, town hall, baths, temples, and an amphitheatre outside the city limits. C. 10.--The forum was flanked by a vast basilica, no less than 325 feet in length by 125 in breadth, with apses of 39 feet radius.[226] A smaller edifice of basilican type is generally supposed to have been a Christian church. It stands east and west, and consists of a nave 30 feet long by 10 broad, flanked by 5-feet aisles, with a narthex of 7 feet (extending right across the building) at the east end, and at the west an apse of 10 feet radius, having in the centre a tesselated pavement 6 feet square, presumably for the Altar.[227] C. 11.--The main street of Silchester ran east and west, and _may_ have been the main road from London to Bath; while that which crosses it at the forum was perhaps an extension of the Icknield Way from Wallingford to Winchester. A third road led straight to Old Sarum,[228] and there may have been others. Silchester lies about half-way between Reading and Basingstoke.