Kyushu (九州, Kyūshū, lit. "Nine Provinces") is the third largest island of Japan and most southwesterly of its four main islands. Its alternate ancient names include Kyūkoku (九国, "Nine States"), Chinzei (鎮西, "West of the Pacified Area"), and Tsukushi-no-shima (筑紫島, "Island of Tsukushi"). The historical regional name Saikaidō (西海道, lit. West Sea Circuit) referred to Kyushu and its surrounding islands.