The Sub-Balkan valleys (Bulgarian: Подбалкански Котловини) of Bulgaria are located between Stara Planina, Vitosha and Sredna Gora. There is great abundance of mineral waters, the most notable spas being Bankya, Sofia, Banya, Pavel Banya, Sliven Mineral Baths, Aitos. They are divided into two parts: western (higher) and eastern (lower).