The uniqueness of the Serra de Tramuntana, which led to its declaration as a World Heritage Site, does not only refer to the exceptional nature of the landscape. Indissolubly linked to it is the interaction of man, remodelling it, preserving it and making it more pleasant and habitable. In particular, the thousand-year-old marshes, which have prevented erosion and made it possible to cultivate the prodigious hundred-year-old olive trees, have been fundamental to UNESCO’s recognition of this uniqueness.