Penarth, United Kingdom offers 3 beaches perfect for sunbathing, surfing, swimming, and more. Penarth is known for the Penarth Pier Pavilion and the beautiful Victorian and Edwardian architecture. The best time to visit Penarth, United Kingdom, is from June to August when the average air temperature is around 18°C (64°F) and the water temperature is approximately 16°C (61°F). Sandee provides detailed maps, photos, and reviews from fellow beachgoers to help you Choose Your Beach™ and plan your perfect beach vacation!