Kawayu Onsen (Wakayama) — relief & relaxation | Compare & book inns

Overview

Kawayu Onsen is a hot spring area located in Hongu-cho, Tanabe City, Wakayama Prefecture. As its name (kawa = river, yu = hot water) suggests, it is nationally renowned for the unique feature of hot spring water welling up when you dig into the gravel of the Oto River bank.

This special onsen has long served as a 'yugoriba' (place for purification with hot water) for pilgrims on the Kumano Kodo pilgrimage routes. While its exact discovery date is unknown, it appears in literature from the Edo period, indicating a long history as a therapeutic spa. Located near the World Heritage Kumano Kodo, it offers the extraordinary experience of digging your own onsen amidst sacred nature. In winter, it becomes lively with tourists flocking to the 'Sennin-buro,' a giant open-air bath created by damming a section of the river.

Typical Spring Qualities and Benefits

The main spring type is a Sodium – Bicarbonate/Chloride Spring. Bicarbonate springs are known as 'bijin-no-yu' (beauty-enhancing waters) for their action of softening the skin's keratin and cleansing it. Chloride springs, meanwhile, are called 'netsu-no-yu' (warming waters) because the salt content forms a coating on the skin, preventing moisture evaporation and providing excellent heat retention. The combination of these two qualities leaves your skin smooth and keeps you warm long after bathing.

• Incisions
• Sensitivity to coldAs a chloride spring, the water is known for its excellent heat retention properties. This helps to warm the body thoroughly from the core, and the effect may last long after bathing, making it beneficial for those who easily feel cold.
• Dry skinThe bicarbonate component, often called a "spring for beautiful skin," helps to soften and gently remove old keratin from the skin's surface. This leaves the skin feeling smoother, while the chloride creates a light veil that helps retain moisture.
• Rheumatoid arthritisThe deep-heating effect of the chloride spring can help to warm joints and muscles, potentially alleviating stiffness and pain. Improved circulation from the warm water may also help reduce inflammation associated with this condition.
• Weakened gastrointestinal function

Water Characteristics and Best Season to Visit

The source temperature is a very high 73°C (163°F), so you mix it with the river water to achieve your preferred bathing temperature. It's the ultimate 'gensen kakenagashi' (direct from the source, free-flowing) experience, allowing you to feel nature's bounty directly. In summer, you can enjoy the onsen while playing in the river, and in winter, you can soak in the famous 'Sennin-buro' for an incredibly open-air experience. The Sennin-buro is only available from December to February, but you can dig your own onsen year-round, making it a destination for all seasons.

Access

Nearby Sightseeing and Local Cuisine

• Sennin-buro (giant open-air bath, winter only)
• Kumano Hongu Taisha Grand Shrine (World Heritage)This is the head shrine for over 3,000 Kumano shrines across Japan and a central point of the Kumano Kodo pilgrimage. As one of the three Kumano Grand Shrines, it has been a major destination for pilgrims for over a thousand years. Its original site, Oyunohara, now features the world's largest torii gate.
• Kumano Kodo Pilgrimage Routes (Nakahechi, Ogumotori-goe, etc.)
• Yunomine Onsen (Japan's oldest public bath, 'Tsuboyu')
• Doro-kyo Gorge (scenic valley views via water jet boat)
• Mehari-zushi (rice balls wrapped in pickled mustard greens)
• Kumano Beef (fine-textured brand wagyu)
• Sanma-zushi (pressed saury sushi, a local festive dish)