Free Hot Springs · Bagni San Filippo · Val d'Orcia
Free hot springs · No charge
The Fosso Bianco
The thermal area of the Fosso Bianco is a generous one. The first pools you come across from the path, as you follow the stream uphill, hold clear and very warm water. Carry on along the trail beside the little river and you reach the White Whale waterfall — a vast block of limestone formed over centuries by the chalky, mineral-rich hot water, which mingles with the stream and lends it that characteristic milky blue-white hue, in striking contrast to the surrounding woodland.
The most famous cascade
The White Whale
The waterfall takes its name from its likeness to a whale's open mouth. It is the most arresting limestone formation at the Fosso Bianco, fed by the hottest water of all — the spring nearby rises at 48°C, warm enough for a bathe even in the depths of winter.
The volume and course of the water spilling over the cascade shift constantly, forever reshaping the scene with fresh forms and colours. In winter the thermal water mingles with rainfall, drawing out shades from green to a russet brown.
Beneficial properties
The Thermal Waters
The waters of the Fosso Bianco are hyperthermal, rich in sulphur, sulphates, calcium and magnesium. The mud that forms naturally as these minerals settle is prized for its benefits to the skin.
Further down the valley, near the spa, the abundant waters of the pool are released into the Fosso Bianco, warming it further still.
The walk
The Woodland Path
The way in begins in the village of Bagni San Filippo. Follow the signs and you join a path that leads into the woods, accompanied by the murmur of thermal water over white pebbles. The first pools lie only a short distance from the entrance; to reach the White Whale, carry on for around ten minutes along the natural trail.
This is no manicured spa — it is nature, pure and simple. Over the years locals and visitors alike have built up small new pools from stones and branches; the lime-rich water sets quickly, forever creating fresh basins to bathe in.
The seasons
When to Visit
Summer — the water runs cooler where it mixes with the stream; pools are plentiful but busy. Best enjoyed early morning or late afternoon.
Winter — the most magical of all: steam rising from the warm water, a hushed atmosphere and few visitors. The White Whale takes on quite different colours.
Spring and autumn — the ideal balance of water temperature, woodland colour and quiet.
Yes. The Fosso Bianco hot springs are completely free and open to the public all year round, day and night. There is no entrance fee — you only pay for parking at the entrance to the village.
Where do I park for the Fosso Bianco?
There is a paid car park (around €1.50/hour) at the entrance to the village, on Via Fosso Bianco, a 5–10 minute walk from the springs. In high season and on spring weekends it fills up quickly, so arriving early in the morning is best.
Are the free hot springs open in winter?
Yes. The Fosso Bianco is open all year, and winter is one of the most magical times to visit: the warm water steams in the cold air and there are far fewer people. The water stays warm whatever the season.
How hot is the water?
The thermal water emerges from the source at around 48–52°C and cools as it flows down the stream, so the pools range from hot near the top to pleasantly warm further down. You can choose a pool at a temperature that suits you.
Is the path suitable for children and older visitors?
The walk from the car park is a gentle woodland path of about 5–10 minutes, manageable for most people, though the ground near the pools can be uneven, wet and slippery. Sensible shoes are advised, and children should be supervised near the water and the delicate limestone formations.
Can I bring my dog?
Dogs are welcome on the path and in the thermal area but must be kept on a lead, and they should not go into the pools — the warm sulphurous water isn't suitable for them, and keeping them out protects hygiene for other bathers.
What should I bring?
Swimwear, a towel and a full change of clothes, sturdy shoes or water sandals, water and a snack, and some cash for parking. Note that the mineral water can lightly stain clothing, so bring things you don't mind marking.
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