The Church of Santa Maria Assunta (commonly called Santa Maria or Santa Maria ad Hortos as it was surrounded by gardens that will become the Horti Leonini) is a sacred building in San Quirico d'Orcia, in the province of Siena, Diocese of Montepulciano-Chiusi-Pienza.
The Church was located on the Via Francigena near the iron gate. Its construction probably dates to the second half of the 11th century. The building is impressive and simple nave with hewn stone travertine small apse with crowning arches and Corbels decorated with animal heads. The roof is wooden trusses; is geared towards the Northwest where you open a small portal.
The most significant is the portal on the Via Francigena that reveals many similarities with that of the Abbey of Sant'Antimo.