The term 'Natural Springs' can be summarized by the crossword solution SPAS, which stands for 'Spa and Sanatoriums'. These are establishments that provide health treatments, such as massage, sauna, and hydrotherapy, using natural springs or mineral-rich waters. Natural springs are sources of water that come from underground aquifers and are naturally heated by the Earth's core. They are often used in spas and sanatoriums to provide therapeutic treatments.