5 Best Sights in Anglesey (Ynys Mon), Wales

The town of Beaumaris dates from 1295, when Edward I commenced work on this impressive castle, the last and largest link in an "iron ring" of fortifications around North Wales built to contain the Welsh. Guarding the western approach to the Menai Strait, the unfinished castle (a World Heritage Site) is solid and symmetrical, with concentric lines of fortification, arrow slits, and a moat: a superb example of medieval defensive planning.

Some historians consider Plas Newydd to be the finest mansion in Wales. Remodeled in the 18th century by James Wyatt (1747–1813) for the marquesses of Anglesey (whose descendants still live here), it stands on the Menai Strait about 7 miles southwest of Beaumaris. The interior has some fine 18th-century Gothic Revival decorations. Between 1936 and 1940 the society artist Rex Whistler (1905–44) painted the mural in the dining room. A museum commemorates the Battle of Waterloo, where the first marquess led the cavalry. The woodland walk and rhododendron gardens are worth exploring. Plas Newydd is not to be confused with the Gothic mansion of the same name in Llangollen.

Opposite Beaumaris Castle is this courthouse, built in 1614. A plaque depicts one view of the legal profession: two farmers pull a cow, one by the horns, one by the tail, while a lawyer sits in the middle milking. Cases are still heard here once a year.

To learn about the grim life of a Victorian prisoner, head to the old jail, built in 1829 by Joseph Hansom (1803–82), who was also the designer of the Hansom cab. Inside you can wander the claustrophobic corridors and view the original cells—including the one that housed prisoners awaiting execution.

Dating from around 3000 BC, this megalithic passage tomb is the most complete site of its kind in Wales. You enter via a narrow opening built into a burial mound. The passage extends for around 25 feet before opening out into a wider burial chamber. The far wall, made of quartz, is illuminated at dawn on the summer solstice. Bring a flashlight, as the tomb has no artificial lighting. Next to the entrance is a replica of a stone pillar carved with Celtic spirals, found here in 1928. The original is in the National Museum in Cardiff. The site is 7 miles southwest of Beaumaris.