Dunleer, Ireland offers 1 beach perfect for sunbathing, surfing, swimming, and more. Dunleer, Connaught, Ireland, is known for its proximity to the Boyne Valley, a UNESCO World Heritage Site featuring the ancient passage tombs of Newgrange, Knowth, and Dowth. The best time to travel to Dunleer, Ireland, is from June to August, when the average air temperature is around 15-20°C (59-68°F) and the average water temperature is about 14-16°C (57-61°F). Sandee provides detailed maps, photos, and reviews from fellow beachgoers to help you Choose Your Beach™ and plan your perfect beach vacation!