Seo Gu, South Korea offers 2 beaches perfect for sunbathing, surfing, swimming, and more. Seo Gu, Gyeonggi do, South Korea, is known for the Gwanggyo Lake Park and the Suwon World Cup Stadium. The best time to travel to Seo Gu, South Korea, is in late spring (May) when the average air temperature is around 18°C (64°F) and the water temperature is approximately 15°C (59°F). Sandee provides detailed maps, photos, and reviews from fellow beachgoers to help you Choose Your Beach™ and plan your perfect beach vacation!