Caerphilly

Long before coal and iron, Caerphilly meant its castle: the fortress Gilbert de Clare had raised in the Rhymney valley from 1268, ringed by artificial lakes, with a small town at its gate. In January 1316 Llywelyn Bren, the Welsh lord of Senghenydd, rose against the royal officials holding the de Clare lands; his men could not break the inner defences, but they burned the town before a royal army defeated him on Caerphilly Mountain. Ten years later Edward II and Hugh le Despenser took refuge in the castle as Queen Isabella's forces closed in, and after the two had fled, its garrison held out until March 1327.

After 1486 the castle declined, eclipsed by Cardiff, and once its sluice-gates failed the lakes probably drained away. When John Leland came about 1539 he found a ruin standing in marshland, with a single tower used as a prison, and from 1583 its tenant Thomas Lewis carried off its stone to enlarge his own house. The town beside it lived on, growing into a market town in the 18th century, and in 1776 the ruins passed to the Marquesses of Bute.