This bath has been present in this town since ancient times. This cave was found in the 13th century, and it was opened to public in the 15th century. It was considered to be a popular spot for bathing when Ottoman Empire ruled over Europe in 16th and 17th century. So the baths have been in operation since a long time, but it wasn't until World War II (in 1941) that the modern version was constructed.
The temperature of this bath is nominal at all times of the year. If you are planning a visit, you should ideally plan from February to December. Try avoiding a trip during January.