Unzen Onsen: Day-Use Hot Spring Baths & Prices

Rising with steam on a plateau about 700 meters high in the center of the Shimabara Peninsula, Unzen Onsen is one of Nagasaki's oldest and most celebrated hot spring resorts. Milky sulfur waters and the dramatic sight of the steaming Unzen Jigoku vents welcome every traveler. Even in summer the air stays cool, and the town has long been loved as a mountain retreat.

Highlights

The greatest draw is the Unzen Jigoku, where white plumes of vapor pour from the ground. Well kept walking paths let you feel the breath of the earth up close, and strolling the jigoku itself is free. Along the sulfur scented trails, stalls sell eggs steamed in the natural vents. The inns nearby let you soak as long as you like in the smooth, milky water.

Enjoying the Seasons

In spring the Miyama kirishima azaleas color the slopes, while summer brings crowds seeking the cool highland air. Autumn offers superb foliage seen from the Unzen Ropeway, and in winter frost flowers wrap the trees in white for a dreamlike scene. It is a mountain spa that changes its face with every season.

Access and Basic Information

Driving from central Nagasaki or the Isahaya area is convenient, and the town makes a fine base for touring the whole Shimabara Peninsula. Bus routes from Nagasaki Station and Isahaya Station also serve the area, so public transport works too. Many inns and public bathhouses offer day use bathing, so the springs are easy to enjoy. The water is a cloudy white sulfur spring with a distinctive scent.

Practical Travel Notes

A leading option for day use bathing is Kojigoku Onsenkan, a public bathhouse said to date from the Taisho era. It offers cloudy white sulfur water welling up right at the source, with admission around 500 yen for adults and 250 yen for children. Hours and closing days can change with the season, so checking the latest information before you go is wise. The Unzen Jigoku paths have some slopes and can be slick with steam, so non slip shoes are reassuring. The elevation is high and mornings and evenings turn chilly, so even in summer a light extra layer keeps you comfortable.

A Quick Tip

The sulfur water is gentle on the skin and warms the body well, but it can discolor silver jewelry, so it is wise to take it off first. Wear comfortable shoes for walking the jigoku trails. Be sure to try the specialties of the steaming stalls, such as eggs cooked in the vents, as you explore.

Practical Information for Your Visit

• Spring quality: Simple sulfur spring (hydrogen sulfide type) / hypotonic, weakly acidic, high-temperature spring. It is said to be good for neuralgia, sensitivity to cold, frozen shoulder, recovery from fatigue and beautiful skin
• How the water is used: The water that wells up directly beneath the source flows freely through the baths just as it is
• Source temperature: 51.1 degrees C
• Day-use bathing (Kojigoku Onsenkan): 9:30-19:00. 500 yen for adults, 250 yen for elementary school children and younger, free for children aged 3 and under
• Closing day: Every Wednesday (open when Wednesday falls on a public holiday). A regular closing day was introduced in August 2024
• Day-use bathing at Seiunso: 11:00-18:00, open all year round. You can use the open-air bath
• Private baths: The private baths at Seiunso are by reservation for overnight guests only, and advance reservations for day visitors are not accepted
• Amenities: Amenities at Kojigoku Onsenkan are charged for. It is safest to bring your own towel and soap
• Parking: Free of charge, space for 200 private cars (shared with Seiunso)
• Access: Get off the Shimatetsu Bus at the "Kojigoku Iriguchi" bus stop, then about a 12-minute walk (about 2 minutes by car). For Unzen Jigoku, get off at the "Unzen Oyama Information Center" bus stop, which is right there
• Walking around Unzen Jigoku: Admission free of charge, open all year round. Allow 1 hour 30 minutes to 2 hours at a leisurely pace, or about 1 hour on a shorter route. There is no dedicated car park, so use one of the paid car parks nearby
• Footing and steps: The walking paths through the jigoku are uneven, and the surface can be wet from the steam. Non-slip shoes are the safer choice
• Time needed: About 1 hour if you only bathe. Allow half a day if you combine it with a tour of the jigoku for a relaxed pace
• What to wear: The resort sits on a plateau at an altitude of about 700 m, and mornings and evenings are chilly even in summer. Bring an extra layer
• A note on what to bring: The sulfur content can discolor silver accessories. It is best to take them off before bathing
• Address: 462 Unzen, Obama-cho, Unzen City, Nagasaki Prefecture 854-0621 (Kojigoku Onsenkan)

Information Sources

The bathing fees, opening hours, closing days and the handling of the private baths are based on the guidance on the official websites of Kojigoku Onsenkan and Seiunso. The spring quality, source temperature and free-flowing use of the water come from the hot spring guidance on the same official websites, while the parking, bus stop, address and the history of Kojigoku Onsenkan (opened in 1919, Taisho 8) were confirmed on the facility page of "Find UNZEN," the tourism information website of the Unzen Tourism Bureau. The free admission to Unzen Jigoku, its year-round opening and the availability of parking also come from that site. The legend of the discovery of the hot spring and the year of designation as a national park are compiled from published materials on Unzen Onsen. As details are subject to change, please check the official information before you set out.