A day-trip hot spring facility located within Chikugo Regional Park along the Yabe River in Chikugo City, Fukuoka Prefecture. Funagoya Onsen was discovered during the Bunka era (1804-1818) and was confirmed to have the highest iron content of any carbonated spring in Japan in an 1886 analysis. The site was once called 'Sparrow Hell' due to its volcanic gas emissions, and legend tells of an ill elderly man who recovered after bathing in these waters. This historic hot spring was visited by famous novelist Natsume Soseki on his honeymoon, and even Emperor Showa and Prince Chichibu stayed here. The water quality is iron(II) and carbon dioxide-containing magnesium-sodium bicarbonate cold mineral spring, characterized by its distinctive brownish color. Known as a 'Beautiful Skin Hot Spring', it is rich in calcium and magnesium, offering calming and skin-beautifying effects. The facility features an indoor bath, rock-style outdoor bath, and reclining bath, with men's and women's sections rotating weekly. During summer, a special outdoor bath using source water at its natural temperature is available. The complex also includes a local products market, restaurant, and free foot bath. It is designated as one of the Kyushu 88 Hot Springs.