The county borough of Caerphilly contains most of the Rhymney River, which formed the original boundary between Monmouthshire and Glamorgan, and continues to the Bristol Channel through Newport, one of seven adjoining counties. Caerphilly is quite small, extending 19 miles north to south and 10 miles west to east, and besides the Rhymney is crossed by several other valleys, separated by long, narrow ridges. The northern reaches are mostly hilly, bordering a small section of Brecon Beacons National Park in Powys, while to the south the valleys widen and the land becomes somewhat flatter.
The only major historic site in the borough is Caerphilly Castle, one of the finest forts in Britain. Nearby is the partly ruined Ruperra Castle, though this is a mansion rather than a true castle, built in 1629.
The only major historic site in the borough is Caerphilly Castle, one of the finest forts in Britain. Nearby is the partly ruined Ruperra Castle, though this is a mansion rather than a true castle, built in 1629.
 The largest Welsh castle; three concentric fortifications, surrounded by lakes and moats, centred on the inner ward with its great hall Rating: ★★★★★ |