Japan (Japanese: 日本, Nippon [ɲippoꜜɴ] or Nihon [ɲihoꜜɴ]) is an island country located off the eastern coast of Asia. It is bordered by the Sea of Japan to the west and the Pacific Ocean to the east, and extends more than 3,000 kilometers (1,900 miles) from the Sea of Okhotsk in the northeast to the East China Sea and Philippine Sea in the southwest. Part of the Pacific Ring of Fire, Japan encompasses an archipelago of 6,852 islands; five main islands (Hokkaido, Honshu, Kyushu, Shikoku, and Okinawa) comprise 96% of the country's total area of 377,975 square kilometers (145,937 sq mi). Japan is officially divided into 47 prefectures and traditionally into eight regions. About three-fourths of the country's terrain is covered with mountains, with much of the remainder made up by flat coastal plains.