I visited Chatsubomi-goke Moss Park on a humid and rainy day. It was not ideal but it gave an interesting atmosphere to the place, making it seem very mysterious.
The entrance fee is 500 yen, but children are free. You can park right next to the entrance and parking is also free. The actual Moss park is a 5 minute bus ride from the entrance, for 100 yen ‘donation’.
The water is so acid that no animals could live there. That is why further down the mountain there is a transformation plant lake. There is a wooden path around the water. When there are a lot of people it can be crowded and slow to go around the park. The park was actually a mine that closed down in 1966. There is no sign explaining the history of the place though. It could have been interesting to know more about the history while visiting there.
While in Kusatsu, it is definitely worth it to visit Chatsubomi Moss Park. With its green variations, waterfalls and mist, it is almost magical.
Around 2 hours from the Kan-Etsu Expressway Shibukawa-Ikaho IC, and an hour from Naganoharakusatsuguchi Station (JR Agatsuma Line). Less than 30 minutes by car from Kusatsu.