Onioshidashi Volcanic Park

One of the most BEAUTIFUL places in our trip. There is actually not many people walking on the trail on the day we went because it was snowing. The trail is easy (made of asphalt) and is not really steep. The full trail is around 1 km long, but we went to the first 510m. The 510m goes to a temple with a refreshing view of Mount Asama, a volcano. Parking is near the bridge to the tickets, and you have to pay a toll if you're from Karuizawa.

Great views of the volcano, a nice walk. Flowers if you time it right. On a November weekday it was deserted with most of the door and restaurants closed. The shrine is inside the paid area. You can also pay for a goshuin after praying. Lots of picnic places, toilets and parking. Must be busy in summer. Overall a bit expensive. Don't go in bad weather.

Oniōshidashi Volcanic Park is an incredible place to witness the raw power of nature. We visited in the morning and was amazed by the landscape — a vast field of jagged black lava rocks formed from the 1783 eruption of Mount Asama. Walking through the trails feels like exploring another planet, with panoramic mountain views and unique rock formations at every turn. The contrast between the dark volcanic terrain and the surrounding greenery is breathtaking. There’s also a peaceful temple dedicated to the Goddness of Mercy Kannon (观音) within the park that adds a spiritual touch to the experience. It’s well-maintained, easy to navigate, and offers great photo spots. A must-visit for nature lovers and geology enthusiasts alike. Do try to spot the luminous moss hidden between the rocks crevices. Suggest to apply sunscreen or sunblock especially when the weather is sunny! Entrance is ¥700 per adult and ¥500 per children. There is also a toll fee of ¥280 in and out of the vicinity.

Onioshidashi Volcanic Park is a truly unique place to visit. The entire landscape was formed by the 1783 eruption of Mount Asama, and walking through the rugged lava fields feels almost otherworldly. The pathways are well maintained and make it easy to explore the area at your own pace. There are clear viewpoints where you can see Mount Asama in the distance, quietly reminding you of the power of nature. It is both fascinating and peaceful, and definitely worth a stop if you are travelling around Karuizawa or the surrounding region. A memorable experience for both adults and children.

A perfect stop between Kusatsu and Karuizawa. Very beautiful in the fall with the colourful foliage making the dark rock look like a fire mountain. The facility is quite run down but still in good working order.

Nice to see little plants growing on the volcanic rocks. It has a scenic view. A few section were closed. My brother accidentally slipped and fell on his back as there was a frozen layer of ice on the path. The puddle of water had frozen from some maintenance / cleaning works.

Although it was freezing and windy. We made a very nice stroll along the scenic trail. The views are amazing. We visited in November and it was autom so the changing colors of yellow, orange and red contrasting the black of the lava rocks was enchanting.

Honestly, the vibe is amazing and the scenery is wonderful. It's so peaceful and interesting. Absolutely recommended. Ps: the souvenir shop at the entrance is totally worth it