This route takes you through some of the medieval hilltowns of the upper Maremma, which are fascinating for the geology as much as for the geography of their buildings. They are made of trachyte, a volcanic rock that was used not only for the external structures but also for the furniture inside.
The use of this rock, which is largely exclusive to this part of Tuscany, adds a dash of colour and elegance to the buildings, thanks to its geomorphic composition. Beloved of architects and aesthetes, it has its own unique style.
Trachyte was used in defensive structures like walls and castles, an example being the forts of Sassofortino and Roccastrada. But it was also used to beautify old town centres, as in the case of Roccatederighi, and in functional buildings like the mill and foundry in Torniella. It therefore has an assured place in the architectural, natural and artistic heritage of the area, and even today reveals itself to visitors in all its beauty, drawing attention to the buildings made from it and their centuries-old functions.