Mt. Komagatake
This volcano dominates the scenery, but the mountain has been off-limits to climbers recently.
Hiking in the area is popular.
The most popular courses through the little islands that dot the southern shore start from near Onuma Koen station, and the time-pressed can even opt for a 15-minute circuit. Ask at the tourist office for a map.
Paddle boats and row boats are available to rent.
There are many hot springs scattered around the shores of the lake.