The most technically perfect medieval castle in Britain, Beaumaris was the last link in the chain of coastal fortresses built by King Edward I to control Wales.

Begun in 1295 in reaction to a Welsh rising, it stands midway by sea between Conwy and Caernarfon, commanding the old ferry crossing to Anglesey. There, in a "beaumareys" ( beautiful marsh), the king commissioned his brilliant architect James of St George to build the biggest and most ambitious of his castles, a perfectly symmetrical stronghold defended by four successive and concentric lines of fortification.

At first work progressed with astonishing speed. Two thousand labourers dug the encircling moat; tools and materials poured into the site in fleets of ships and trains of carts; and hundreds of masons, smiths and carpenters began raising the six towers and two huge gatehouses of the inner ward, surrounded by sixteen-towered outer defences.

However, the king's attention despite the architect's anguished pleas - "Sirs, for God's sake be quick with money for the works...." - funds and supplies faltered. When work petered out some thirty years later Beaumaris was still not quite complete.

With its fourteen successive barriers between outer gate and inner ward, its hundreds of cleverly positioned arrow slits, its "murder-holes", wall passages and uniquely designed latrines, Beaumaris is the most fascinating of all Edward's castles to explore. A World Heritage Listed Site.