Summer Spa, which dates back to the Eastern Roman Empire period, is located in the Ilıca Stream bed in Gölcük district. It is believed that the water that comes out of here is good for psoriasis and stomach ailments. Summer Spa, which was also used as a health center in the Byzantine and Ottoman periods, provides hourly service with different room types within the scope of thermal tourism today. You can also benefit from the Turkish bath, pool, sauna,
and steam room within the facility.