Lonely Planet review
To get a sense of the lake's enormous scale, you really need to leave the shoreline. Formed by a series of violent volcanic eruptions eons ago, Towada-ko is a roughly circular caldera lake hemmed in by rocky coastlines and dense forests. In the autumn months, the dying leaves erupt in a fiery display that stretches to the horizon.
From the docks in Yasumiya, you have a couple of options for scenic cruises, the best of which is the one-hour circuit between Yasumiya and Nenokuchi (one way ¥1400). Boats leave roughly every hour from April to early November between 8am and 4pm. There is also a year-round 40-minute loop-circuit (¥1100), which is preferable if it's too cold to hike for extended periods along the Oirase-gawa.