Gahanive, Ireland offers 2 beaches perfect for sunbathing, surfing, swimming, and more. Gahanive, Munster, Ireland, is known for the Gahanive Castle and the annual Gahanive Music Festival. The best time to travel to Galway, Ireland, is from May to September, with average air temperatures around 50-65°F (10-18°C) and water temperatures around 55-60°F (13-16°C). Sandee provides detailed maps, photos, and reviews from fellow beachgoers to help you Choose Your Beach™ and plan your perfect beach vacation!