Lake Shikotsu is a caldera lake located in Hokkaido, Japan. It is the second deepest lake in Japan and the seventh deepest in the world. The lake is surrounded by mountains and forests and is known for its clear blue waters and scenic beauty. There are hot springs and ski resorts in the surrounding areas, making Lake Shikotsu a popular tourist destination. Activities like boating, fishing, hiking, and camping are also popular around the lake.