Wedged between the Menai Strait and the purple mountains of Snowdonia, Caernarfon is home to Wales’ most magnificent castle, designated as a World Heritage Site. The town’s focus is the castle, located by the river. It was built between 1283 and 1301 and was Edward I’s most impressive stronghold. Near the castle is Segontium Roman Fort, a significant Roman fort dating to AD 77 and now housing a small museum. For families there is Greenwood Forest Park, a 7 hectare site with a slew of rides, activities, and attractions. One thing not to miss is the Green Dragon, the world’s first people-powered roller coaster. Running between Caernarfon and Rhyd Ddu is the vintage Welsh Highland Railway, another of Wales’ restored narrow-gauge railways.