Lake Hévíz is one of the easiest and best excursions from Keszthely: a natural thermal lake in the spa town of Hévíz, about 8 km away. The water stays warm enough for bathing year-round, and the bathing complex is organised around the lake rather than replacing it.
It is a classic Hungarian health-resort experience, with a slightly old-fashioned rhythm that suits the place. Bring sandals, a towel, and patience for peak summer queues. In cooler months the steam above the water makes the visit more atmospheric.