The "submerged forest" can only be seen for two months in spring at Lake Shirakawa in Iide Town, Yamagata Prefecture. Every spring, large amounts of melting snow from the Iide Mountain Range flow into the lake.
In order to give visitors a bird's-eye view of the submerged forest, where snow still remains, a hot air balloon ride was held. The submerged forest can be enjoyed until mid-May, and there are also experiences such as riding a canoe through the trees.