Especially in the twelfth and thirteenth centuries, the hillsides of Tuscany contained many rudimentary hermitages, some of which were natural caves.
Tradition has it that there was a hermit’s cave near the present site in Rosia, which was superseded by dwellings on the present site once numerous hermits came to the area.
In 1969 the site was excavated through the cooperation of Wayne State University, Northern Kentucky University, the Tuscan American Foundation and the Etruscan Foundation (all from the United States of America).
A coin minted in Germany in the year 1002 was discovered on the site. This site at Rosia was very probably inhabited for before then, however, because tombs were found there dating from the tenth century, and walls underneath the house have origins in the ninth century.
Beneath the ruins of the present church there had successively stood two wooden churches, plus an adjacent cloister for a community of hermits.
Archaeological evidence indicates that both churches had been destroyed by fire. Even the wind direction during the last fire has been deduced as coming from the south-east, which is the usual prevailing wind direction at Rosia.
