Sao Pedro da Cadeira, Portugal offers 7 beaches perfect for sunbathing, surfing, swimming, and more. Sao Pedro da Cadeira, Lisbon, Portugal, is known for its proximity to the scenic landscapes and cultural heritage of the Lisbon region. The best time to travel to Sao Pedro da Cadeira, Portugal, is from June to September, with average air temperatures around 70-80°F (21-27°C) and water temperatures around 64-70°F (18-21°C). Sandee provides detailed maps, photos, and reviews from fellow beachgoers to help you Choose Your Beach™ and plan your perfect beach vacation!