Duomo di Tolmezzo, Cathedral in Tolmezzo, Italy.

The Duomo di Tolmezzo, dedicated to Saint Martin, stands on Piazza XX Settembre with a facade left unfinished for lack of funds. Inside is a single large nave with six side chapels, three per wall, and a raised presbytery under a dome frescoed by Pietro Antonio Novelli with the Holy Trinity. The bell tower, reworked from the belfry up in 1921 by Filippo Filliponi, is topped by a weathervane angel of 1848.

The present church was built from 1764 on the site of the old church of San Martino, demolished to make room for it; the design was by Tolmezzo-born Domenico Schiavi with Francesco and Antonio Schiavi. Work stopped for lack of funds and the facade was only finished in 1931. The 1928 earthquake badly damaged the building, which was rebuilt in 1931 with changes to the original plan. The bell tower predates the 18th-century reform; from the belfry up it was altered in 1921 by Filippo Filliponi.

The church is dedicated to Saint Martin and is the seat of the archdeacon of Carnia, shared with the parish church of Santa Maria Oltre But. In the Chapel of Sant'Ilario, the marble altar mensa carved by the Filipuzzi brothers holds relics of Saint Ilario, patron of Carnia, brought to the region in 1656. The painter Nicolò Grassi included a portrait of his patron Jacopo Linussio in his cycle of the Twelve Apostles; the portrait is kept in the sacristy.

The cathedral stands on Piazza XX Settembre, on the site of the older church of San Martino demolished to make room for it. The facade was only finished in 1931, so the front and the 1921-modified bell cell, topped by the 1848 weathervane angel, are the exterior features to look for. The building is an active parish church, so visits fit around services.

The dome fresco of the Holy Trinity is by Pietro Antonio Novelli, painted between 1765 and 1785. The painter Nicolò Grassi included a portrait of his patron Jacopo Linussio in his cycle of the Twelve Apostles; the portrait is kept in the sacristy.