A Ghjesgia di a Trinità di San Giovani... This building dating from around 1100 is an absolute gem of Romanesque Art.
The granite blocks constituting its facade are of 3 different colors, 3 being the number of the perfection of the Trinity: beige symbolizes the Father, green, the Son, and red the Holy Spirit.

Above the door, an arch has 7 dark keystones and 8 light keystones: the 7 invites man to turn to God and the 8 symbolizes his resurrection.
Inside are 2 15th century frescoes.

The Church had the status of a Piévane Church. It served as a burial place for the inhabitants of Aregnu and Sant'Antuninu until the beginning of the 19th century in a communal burial place called "arca". His religious vocation was coupled with a role
social until the beginning of the 16th century.

It also served as a court of first instance. The name of the village, Aregno, would be a deformation by palatization of aringo.