The free thermal baths of Petriolo are famous free baths in Tuscany, second only to Saturnia.
How to get to the baths
The free thermal baths of Petriolo are easily reachable from the Grosseto-Siena highway, about 40 km from Grosseto.
They are right under the bridge over the Farma. After crossing it you will find the road that goes down to the limestone thermal pools, formed along the river, which collect the excess water not used by the paid thermal establishment, built a few meters away.
Properties of thermal water
The temperature of the hot water, at the source, is 43 degrees Celsius. Its unpleasant smell is due to the strong presence of sulfur. But it is for the content of many other mineral salts (free carbon dioxide, calcium, fluorine and chloride ions, sulfate and hydrogen carbonate) as well as for the temperature, that Petriolo water has been defined as hyperthermal.
These characteristics give the thermal water of Petriolo multiple therapeutic properties recognized since Roman times, indicated in various chronic pathologies: osteoarticular diseases, chronic arthropathies, skin diseases such as acne, psoriasis, eczema and respiratory tract diseases such as pharyngitis, sinusitis and rhinitis.
It is also possible to dive and swim in the nearby stream enjoying the benefits of the frigidarium-calidarium effect which is obtained by passing in sequence from the warm waters of the thermal spring to the cold ones of the Farma river.
A bit of history
In antiquity they were also much more prestigious than in Saturnia.
Cited by Cicero to witness the ancient attendance.
The name Petriolo is from the Middle Ages (from petria - wooden funnel) due to its shape, almost like a funnel.
As it is still visible from the ruins near the thermal spring, Petriolo represents in history a very rare case of "fortified thermal baths". In fact, the residual wall abutments belong to the ancient “Castello di Petriolo”, a defensive structure erected to protect the spring and the baths, considered to be so precious that they cannot be left at the mercy of threats from the powerful of the surroundings.
The renown of its waters is evidenced by the visit for curative purpose of Pope Pius II, who came here to heal the "podagra", a disease he suffered from and which prevented him from walking without pain.
The Republic of Siena charged a gabelle on the use of the Petriolo baths, an almost unique case among the various free Italian baths, bearing witness to the extraordinary value attributed to these medicinal waters.