The Fortress´s Museum
Today a museum, the Fortress is first and foremost a valuable example of military architecture. The mountain on which San Leo rises, for its towering position over the valley below and its geographical features, with steep stone walls perpendicular to the floor, has always been a natural stronghold. The Romans, well aware of its strategic value, built there a first fortification. During the middle Ages, the fortress was fought over by the Byzantines, the Goths, the Lombards and the Franks.
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In one room of that museum is also a collection of minerals