Dyffryn Ardudwy is a village and community in the Ardudwy area of Gwynedd, Wales. It has a population of 1,654.
The village of Dyffryn Ardudwy is situated on the A496 costal road between the towns of Harlech and Barmouth and at the foot of Moelfre, part of the Rhinogydd range.
There are a number of prehistoric cromlechs in and around the village they are some of the earliest tombs erected on these islands. Dating from around 4000 BC the cairn at Dyffryn Ardudwy has two separate burial chambers. Nearby is an avenue which was built by the powerful Vaughan dynasty, (who were instrumental in placing Henry VII of England on the throne in 1485), to connect their family mansion, Cors-y-gedol (The Bog of Hospitality), with the family chapel. The existing mansion was built in 1576. Nearby, the Cors-y-gedol burial chamber stands amidst the site of ancient fields and settlements and the area affords glorious views of Cardigan Bay.