The 63 Building (Hangul: 63 빌딩 or 육삼 빌딩), officially the Hanhwa 63 City, is a skyscraper on Yeouido island, overlooking the Han River in Seoul, South Korea. It was designed by the American architectural firm Skidmore, Owings & Merrill (SOM). At 250 meters (819 ft) high, it was the tallest building outside North America when it opened in July 1985, and remains the tallest gold-clad structure in the world.