British remains in Sussex are but scanty. A few of the larger and more elevated of the hill-camps, and those of irregular form, as Cissbury, which includes 60 acres, are supposed to be the work of the Regni, the earliest recorded inhabitants of the district. It is also difficult not to see in the Arun, the Adur, and the Ouse, names corresponding to the Aeron, the Dour, and the Usk or Esk, by which many streams in Celtic countries are still designated. Glynde has been claimed as a Celtic name, but it is very rare, especially in Sussex, to find the name of a parish of other than Teutonic origin. Of the Roman period the traces are more numerous. The main road intersecting the county from Chichester towards London is undoubtedly of that date, and there seems to have been at least one other from Chichester—the Roman Regnum—to Pevensey. There remain also several rectangular camps, as Goushill, Hollingbury, Ditchling, Highdown, and Brighthelmstone Down, evidently Roman. Chichester, though its Latin name probably includes an earlier appellation, has the Roman cruciform arrangement of its two main streets, though not the rectangular outline. Anderida, Mutuantonis, and Mida, Roman towns of which the site is disputed, seem to have been in Sussex; and at Bognor and other places, pavements and foundations and inscribed stones, and other marks of Roman habitation, have been discovered. Still the remains, whether of British or Roman occupation, are but slight: all that speaks of law, of order, of property, of the family tie, of the forefathers of the people, of civil or religious polity, and of public worship—all of this character which is ancestral, is English. This thorough uprooting of the traces of earlier occupation is due, no doubt, to the position of Sussex upon that part of the British coast most exposed to Saxon and Danish invasion, and which bore the attacks of those formidable invaders when at their earliest and fiercest. Sussex was late to come under the humanising influences of Christianity, remaining Pagan till the middle of the seventh century. The remarkable conservation, to our days, of the names and divisions is probably due to the very peculiar configuration of the district, and to the isolation produced by its steep and lofty frontier ridges, and by the dense woodland which covered, and to some extent does still cover, its central part. As the position of the principal castles is determined by this configuration, a few words concerning it will not be out of place.