Kōnan is a city located in Kōchi Prefecture, Japan. As of 30 June 2022, the city had an estimated population of 33,076 in 15350 households and a population density of 49 persons per km2. The total area of the city is 126.46 square kilometres (48.83 sq mi).

The Tosa Kuroshio Railway Asa Line is a 42.7 km Japanese railway line operated by the third-sector railway operator Tosa Kuroshio Railway. It connects Gomen Station in the city of Nankoku with Nahari Station in the city of Nahari in Kōchi Prefecture. The line is also commonly known as the Gomen-Nahari Line (ごめん・なはり線).