The church of San Martino that no longer existes was older than San Pietro. It was probably built on the top of the hill above the current chapel of San Rocco. The settlements in Castellazzo and Miravalle are in fact, together with the Angrisana locality, the oldest in the area of the current Municipality of Portacomaro.
On the left side of the church there is a granite plaque walled up on the left side of the facade of the church of San Pietro, bearing an inscription in Roman lapidary style of votive argument that could have come from this ancient church that has now disappeared. In the 15th century, the development of Portacomaro inside and around the shelter and the construction of the new parish church of San Bartolomeo deprive these two ancient churches of their importance. The two churches are in fact placed outside the inhabited area of Portacomaro (extra terram ipsius loci) in a document dated 1585. In the year 1583 the church of San Pietro was downgraded to a cemetery church. In a description of its conditions dated in that year, the absence of the floor, the presence of a vault above the altar and the collapse of the architrave of the portal that forces to block the main entrance (Desuper altare ipsa testudina est, in ceteris partibus non, est absque floor ... porta clausa propter ruinam minantem). The structure of the church is however solid if the threat of ruin hypothesized in the document has not occurred to date, considering that the hill on which St. Peter rests has been hollowed out three times. A first time in the south to trace the current Viale Dr. Degiani, then to the west to build the villa Degiani, finally to the east and north to build the sports field and the relative access road.
The maintenance of the church until 1836 appears to be due to the Municipality and the conditions then appeared fair, the church was occasionally used to officiate religious rites. Memory of its original parochial functions also survived ('est parochia / is antiqua et spectat ad communitatem, quoad materiali tolerabiliter se habet').
In 1910 the cemetery of San Pietro was closed and the buried bodies were moved to the current cemetery of San Rocco The church was deprived of most of the tombstones that were walled up on its sides and deconsecrated.The church of S. Pietro until a few years ago, still to be restored, was indicated as a monument in a state of neglect. Fortunately, in recent years, the roofs have been restored, the interiors, the access routes, and the paintings from the 16th / 16th century have been restored. It is a precious monument today used for special events.