Nankaidō (南海道; Japanese pronunciation: [naŋ.kaꜜi.doː], lit. 'Southern Sea Circuit') is a Japanese geographical term. It means both an ancient division of the country and the main road running through it. The road connected provincial capitals in this region. It was part of the Gokishichidō system.
The Nankaidō encompassed the pre-Meiji provincial lands of Kii and Awaji, plus the four provinces that made up the island of Shikoku: Awa, Sanuki, Tosa, and Iyo.