Aberconway, or Snowdon Castle in Carnarvonshire, must have been one of the most formidable specimens, from the great extent of its curtain walls, and its numerous round towers. It was built, say authorities on which we place no reliance, except in so far as they correspond with the character of the edifice, in 1284; it served the purpose for which the strongest fortresses are required—that of a frontier defence. In Flintshire there are Hawarden and Rhudland. Beaumaris, in Anglesea, has some fine diminishing towers. Carew, in Pembrokeshire, has a sort of angular buttresses, instead of the graceful increment towards the base, in the round towers; but it is a luxuriant and noble specimen; and though Welsh tradition says it belonged to the princes of South Wales—no man can tell how many hundreds of years before William or Rollo either—and was given by Rhys ap Theodore, with his daughter, Nest, as a marriage portion to Gerrald de Carrio, yet we take the liberty of holding that it as clearly bears the mark of the invader of Wales, as any government-house in Canada or New Zealand bears evidence that it is not the work of the natives. We take Cilgarron, Haverford-west, and Mannorbeer castles, in the same county, to belong to the same category. The same characteristics do not so frequently occur in the southern English counties, though there is Pevensey in Sussex, Goodrich in Herefordshire, and Cowling in Kent, and there may be several other instances. They reappear on the Border, where they were connected with the Scottish wars; the forms may be seen in Prudho, Twizel, the outworks of Bamborough, and in a modernised shape at Alnwick.