Derrynane, Ireland offers 2 beaches perfect for sunbathing, surfing, swimming, and more. Derrynane is known for its stunning beaches and the historic Derrynane House, the ancestral home of Daniel O'Connell. The best time to travel to Derrynane, Ireland, is from June to August, with average air temperatures around 15-20°C (59-68°F) and water temperatures around 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!