Natural Hot Spring Heiwajima

Heiwajima Natural Hot Spring, known locally as Heiwajima Onsen, is a popular bathing facility located in Ota Ward, Tokyo. The hot spring draws its waters from 1,500 meters beneath the earth's surface, bringing up natural sodium chloride waters that are believed to have therapeutic properties. The facility opened in 1983 and has since become a favorite retreat for Tokyo residents seeking relaxation without leaving the metropolitan area.

The hot spring water contains a high concentration of minerals, particularly sodium and chloride, which give it a distinctive golden-brown color. These mineral-rich waters are reputed to help with muscle fatigue, joint pain, and skin conditions. The facility maintains the water at temperatures between 40 to 42 degrees Celsius, providing an authentic onsen experience. What distinguishes Heiwajima from many urban hot springs is that it uses genuine natural spring water rather than heated tap water, making it one of the few authentic hot springs accessible within Tokyo's 23 wards.

Visitors can experience both indoor and outdoor bathing areas, with the outdoor bath offering a rare opportunity to enjoy hot spring bathing under the open sky in central Tokyo. The facility includes several bath types beyond the main hot spring pools, including saunas, cold plunge pools, and jet baths. Traditional Japanese bathing etiquette applies, meaning visitors must wash thoroughly at shower stations before entering any communal bath. The onsen is gender-separated with distinct facilities for men and women.

The complex also features dining options serving Japanese cuisine, relaxation lounges, and massage services. Many visitors spend several hours at the facility, treating it as a comprehensive wellness experience rather than a quick bath. The atmosphere remains distinctly local, attracting neighborhood residents and Japanese tourists more than international visitors.

Heiwajima Onsen is located approximately 15 minutes by foot from Heiwajima Station on the Keikyu Main Line. Alternatively, visitors can take a free shuttle bus that runs from the station to the facility. From central Tokyo stations like Shinagawa, the journey takes roughly 20 minutes by train. The admission fee is approximately 2,500 to 3,000 yen for adults, with additional charges for towel rental and optional services.