Duke Luigi Strozzi donated the church to the community in 1682 and the building cost more than twelve thousand scudi. From 1675 he had started a series of purchases and exchanges with the inhabitants of the village and the houses near the castle of Forano, to change the urban plan of the town. In fact, with the donation of the Church of the S.S. Trinity, the Duke asked in return for citizens of Forano to assign all rights to the old church of St. Mary (also known as the Transit) from1313, that was located in the old village next to the Baron's Palace. It is likely that the Duke wanted to add light to the passage near the palace and to create a new possibility of urban development in the country. The church is in Baroque style and the interior has a nave with three chapels on each side, ending with an apse.