Amami Onsen (hot spring), near the Nankai Koya Line Amami Station, is located in a mountainous area close to the border with Wakayama Prefecture. This hot spring was opened in the early Northern and Southern Courts period in the 14th century. Ancient pilgrims to Mt. Koya made a stopover at this hot spring to heal their travel fatigue, calling this spa Gokuraku-buro (paradise bath). The water comes from a simple radioactive spring (25°C), believed to be effective for chronic gallbladder inflammation, gallstone diseases, neuralgia, gastrointestinal disorders and more. Amami Onsen can be enjoyed at the sukiya-style Japanese inn Nanten'en, which is located by the Amamigawa River and boasts a Japanese garden of 3,000 tsubo (1 tsubo = approx. 3.3 m2). The inn's main building is the former annex of Shioyu, which operated in Ohama, Sakai City. This building, relocated from Ohama, was originally designed by Kingo Tatsuno, a renowned architect in the Meiji period, who is known for designing the Central Public Hall on Nakanoshima in Osaka City. This main building of Nanten'en was registered as a national tangible cultural property.