The largest lake in Japan is Lake Biwa, located northeast of Kyoto. Surrounding the lake, there a loads of small Japanese towns and cultural places to visit. The place that stood out for me was Hikone, a castle town with on one side mountains and the other side the lake.
Like Odawara, the castle is the main attraction of the city. In Hikone, the castle and its park are next to the lake so in addition to experiencing the culture, you can experience nature as well. The castle is located a bit higher up from the top of the building you got a great view across the surrounds. To the west is the lake, and as the sun goes under at that side, beautiful sunsets can be seen from Hikone castle tower. The north and south of Hikone are also flat, so on a clear day you are able to see far in the distance.
The main street in Hikone city, leading from the castle to the station, is also popular among local tourists. It hosts a great amount of shops and restaurants with a cozy atmosphere. A walk from the station to the castle ground is around 20 minutes. Access to Hikone is good with 5 minutes by train to Maibara Station, a Shinkansen station between Kyoto and Nagoya.
A regular train from Nagoya is also very doable. Especially in winter, when going through the mountains on a snowy day is a unique experience. Even in winter it can be snowy in Hikone, so whether go in summer and again in winter, the atmosphere will be completely different. In spring there is also a cherry blossom festival in the castle park. So Hikone is certainly worth visiting more than once.