The parish of Sts. Fabian and Sebastian was mentioned in the Statute as the church of Sv. Marija (St. Mary) round which the settlement first began to form. During the course of frequent Turkish attacks and hostility, this church was fortified in 1535, and it has remained in the shape of a church-fortress up to the present day. The white stone facade, which was added to in the 19th century, camouflages the fine Renaissance outline of this fortified church to a certain degree.
In the courtyard of the church there is an archaeological collection where the stone remains from various periods of the past of Jelsa are kept.
The interior of the church has three aisles. There are some tombstones from the 16th century on the floor. On the high altar there is a wooden sculpture of Our Lady, which was brought from Citluk near Sinj. In the south chapel is a painting of Our Lady and St. Sebastian by Pietro de Costera (1612-1702), a baroque painter from Venice of Flemish origin.
In the sacristy there is a valuable vestment, altar furnishings, and several
wooden crosses.