Horai Island (蓬莱の島 Hōrai no shima), also called Penglai Island, is an artificial island off the coast of the Chinese Federation, which generates electricity through tidal activity. It is granted to the Order of the Black Knights by the Federation to accommodate the Japanese refugees exiled following Britannia's second attempt to establish the Special Administrative Zone of Japan. It was later established as the temporary capital of the United States of Japan and United Federation of Nations. It also serves as the Black Knights' primary base of operations. It is named after Mount Penglai.