The little Church of San Sebastiano in Lesa on the shore of Lake Maggiore is a rare example of a Romanesque church which has retained its original structure through the centuries, without significant additions or alterations.

Built between 1110 and 1125, probably to assert the right of Lesa to control an essential transit point, it stands on a small hill dominating the oldest crossing of the river Erno. ?

The remains of some Roman tombs (now lost) were found around the church, suggesting, as popular tradition holds, that the victims of some unknown epidemic of the past may have been buried in this sacred spot.

The church comprises an apse, divided into three parts by pilaster strips, and a single east-facing nave. The three-storey bell tower is incorporated into the body of the church, and has windows increasing in size towards the top: narrow slits on the first level, single-lancet in the middle and double-lancet at the top.

The wall above the apse has a cruciform window corresponding to a fresco symbolising “Christ the Light”, an extremely original depiction of the theme of redemption through the risen Christ, in which the window aperture forms the body of the Saviour with His outstretched arms painted at the sides. At the top are the sun and the moon, and at the bottom, representing the people of God, two sheep angled towards the central figure.