Somani Dam is a 44-meter-high gravity concrete dam built by Hokkaido in 1975 for the purpose of flood control in the lower reaches of the Somani River. It is also a well-known cherry blossom viewing spot, with the best viewing time in early to mid-May, making it one of the places in Japan where the cherry blossom viewing season begins later than any other place in Japan.

In summer, camping and river fishing can be enjoyed. This campground is a hole-in-the-wall with few visitors, so it is recommended for those who want to have a great time with their friends. There is a kitchen, but please note that it does not provide drinking water. The toilets are pumping type.