The sources thermales (thermal springs) of Cilaos were first brought to the attention of the outside world in 1815 by a goat hunter from St-Louis, Paulin Técher. A track into the Cirque was constructed in 1842, paving the way for the development of Cilaos as a health spa for rich colonials. The spring is heated by volcanic chambers far below the surface. It's said to relieve rheumatic pain, among other bone and muscular ailments.
The old thermal station was opened in 1896, but the spring became blocked in a cyclone that occurred in 1948. The project was revived in 1971, only to close in 1987 because of damage to the buildings caused by the chemicals in the spa water. The latest incarnation of the Cilaos spa is the Thermes de Cilaos at the north end of town. Several health treatments are offered, including a 20-minute hydromassage (€15). This is a perfect way to rejuvenate tired and sore muscles after your hike.
