The church was built between the end of the 13th century and the beginning of the 14th prbably due to a miracle performed by St. Francis.
Tarchna, Corneto, Tarquinia
Legend has it that the miracle occurred in the area where an oratory, dedicated to the Trinity, once stood and was officiated by the Franciscan Friars Minor. At the beginning of the 16th century the church underwent massice restoration, completely altering its original structure. However, in 1959 the National Trust in Lazio ordered that the church be totally restored as closely as possible to its original design. The structure presents both Gothic (particularly inside the church) and Romanesque (mostly on the facade) architectural features. The facade is divided into three sections corresponding to same partitioning inside the church. In the higher central section of the facade there is the main portal adorned with four concentric receding pointed arches which are clearly Gothic in style. Above the portal there is a large decorative rose window which is undoubtedly Romanesque in style. The shorter sections on either side are decorated with blind arches along the top perimeter: the ones on the left are Lombard while the first six on the right are Gothic. The bell tower was constructed in 1612, most likely replacing a former bell-gable with three bells. The interior of the church is divided into a nave and two aisles with five bays each. The nave is twice as big as the aisles and the transept is slightly raised, leading to three apses at the rear end of the church. Five chapels were added on the right between the 15th and 16th centuries: the Chapels of Blessed John of Triora, Mary Immaculate, St. Anthony of Padua, the Nativity Scene, and the most recent, Fallen Soldiers. The convent housed the “Galileo Galilei” Science High School until the end of the 1970s when it became home to the “Frati dell’Immacolata” (Friars of Mary Immaculate). The Renaissance cloister and well, situated in the gardens, are remarkably beautiful and worthy of note.