The main mineral baths; built in the year 1913, were built in a modern Bulgarian style in place of the pre-existing Turkish baths. They are located on their own water source; the building does not require artificial heating for its rooms or water. During the time it was built, there was a large pool and 4 smaller ones. Due to the development of the area, the baths were experiencing a steady drop in attendance and eventually closed to the public. Even so, residents of Sofia still frequent them today to get hot water from the ancient hot springs. The city has been famous for its hot and cold natural hot springs since antiquity. In and around Sofia are found more than 40 mineral springs grouped into 8 sectors, each producing 550 liters of water per second with a temperature of 45 to 60 degrees Celsius. The water from this spring will be may be used to provide heat to many public buildings. The baths are in a process of reconstruction for the Sofia History Museum, and for use as a Spa center.