A mineral springs spa has a source of natural mineral water that you can soak in. Mineral springs have been valued for thousands of years for their power to ease joint pain, arthritis, and other physical ailments.
Mineral springs may come out of the earth at a tepid temperature and then be heated for bathing. If there is a lot of geo-thermal activity, the mineral water is literally heated by the earth and is called a hot springs. Sometimes the water is so hot it has to be cooled.
Mineral springs have naturally occurring minerals and trace elements such as calcium, magnesium, potassium, sodium, iron, manganese, sulphur, iodine, and bromine. The exact makeup of the water vares from spring to spring, and many spas post the exact chemical make-up. Different waters are considered beneficial for different ailments.
Mineral springs spas vary greatly in the degree of luxury and amenities they offer. Some are historic bathhouses where you go to soak for 20 or 30 minutes in a private room that may be very simple. Usually you can get a massage. There might be communal outdoor pools. But some of the world's most lavish hotels and resorts were built on the site of mineral springs.
Some of the world's great spa cities rose up because of mineral springs, include Baden-Baden in Germany, Spa in Belgium and Bath in England. The U.S. has its share of historic spa cities that sprang up in the 18th and 19th centuries, including Berkeley Springs, Virginia, Calistoga, California and Hot Springs, Arkansas.
In the 18th and 19th centuries drink the mineral waters was an important part of the cure. This was a time when the wealthy classes went to spas to mingle, and the sipping pavillon provided the perfect opportunity. Today most people prefer a good soak to drinking the pungent, odd-tasting waters.