Opened in 1956 by Nankai from Wakayamashi to later Chikkōchō (then Wakayamakō) for rail connection to its ferry to Shikoku. In 1971 the line was extended to Suiken via present Wakayamakō, by Wakayama Prefecture for the expansion of the port and to provide freight access to then planned lumber transport. The section between Wakayamakō and Suiken was closed in 2002, until then freight train had never operated. The stations between Wakayamashi and Wakayamakō were abandoned in 2005 due to few passengers, then Kubochō Station was renamed the "Prefecture-Company Boundary" (県社分界点,Ken-sha Bunkai ten?).
All trains are operated for the connection to and from Nankai Ferry.
Limited express trains named "Southern" and express trains run through to and from Namba, and local trains run between Wakayamashi and Wakayamako. 2 Namba-bound express trains were changed to the local trains to Wakayamashi on October 1, 2012. The 2 express trains start at Wakayamashi.
Weekends and holidays
6 round trips are operated; 4 are limited express trains named "Southern" which run through to and from Namba, and the other 2 are local trains running between Wakayamashi and Wakayamako.