The British earthwork, Cefn Carnedd by name, from its bastion-like hill between the Carno and the Severn, commands a beautiful view overlooking both valleys. In plan it is a blunt-ended oval, the longer axis lying nearly east and west; on the latter side and towards the north it is enclosed by a triple ditch and rampart, but on the southern side a single entrenchment, owing to the steepness of the hill, suffices for defence. The enclosed area, about 300 yards in length, rises slightly towards the west, and at this end about one-third of the whole is cut off by a ditch and rampart, apparently with the intention of forming a kind of keep. Entrances may still be found and the approaches traced; these evidently were cunningly devised so as to be commanded by the defences; in fact, this must formerly have been one of the strongest and most formidable among the hill-forts of Britain. There are others in the neighbourhood, though these are inferior to Cefn Carnedd. The Roman fortress, Caersws by name, is in the valley on the opposite bank of the Severn, at a distance of some 300 yards from the river. This, too, must have been in its day a place of great strength. It was enclosed by a high quadrangular rampart, with a ditch outside, which still remains in most places, though they have been injured here and there, and one angle of the _vallum_ has been destroyed to make a site for the railway station. Caersws, the Mediolanum of Tacitus, evidently was once a stronghold of great importance, for three Roman roads converge to it. The strategic advantages of the position are obvious. The valley of the Severn is now broadening, and its scenery becomes richer and more fertile, although bare hills still rise in the background. About four miles lower down another manufacturing town is reached, which, however, is considerably smaller than Llanidloes. This is Newtown, a place comparatively modern--as the name implies--which, however, has a certain commercial status as the recognised centre of the Welsh flannel trade, but is otherwise uninteresting, except for a carved rood screen and one or two more relics of an older building preserved in its modern church, and for being the place where Robert Owen, the father of modern socialism, was born and was buried.