The village of Pessano that as Paerno, helped people, in 1250, the village of Bollengo, disappeared quickly, while the Romanesque church of the village, protected by the Chapter of the Cathedral of Ivrea, has been preserved to this day. The facade has a centrally located bell, according to the type clocher porche (androne bell); from here it leads to the single nave apse, divided into two spans by a wide arch; on the walls there are remains of frescoes dating back to the fifteenth century and a very old fragment of hurdle with a geometric design pattern. On the right side of the building there are two rooms of the rectory added more recently. The bell tower is spread over six floors and has five backgrounds separated by pilasters and suspended arches; opening to the third floor slit happen nell’alzato a lancet and two orders of windows.