Duomo vecchio, Romanesque cathedral in San Severino Marche, Italy.

The duomo vecchio, or old cathedral, stands on Monte Nero in San Severino Marche. Its 14th-century facade has a rounded portal, a three-light niche with trilobed arches and an oculus, and a band of small hanging arches. The square bell tower, attached to the left of the facade, has four large bifora windows and a frieze of trilobed arches.

The cathedral was founded in 944 on Monte Nero and underwent major reconstruction in 1061. By the late 13th century it received its present Romanesque-Gothic form.

The wooden choir stalls were begun in 1483 by the local carver Domenico Indivini and completed in 1513 by the Acciaccaferri brothers. The church is still called duomo vecchio to distinguish it from the newer cathedral of Sant'Agostino in the valley below.

The church stands on the summit of Monte Nero, in the medieval upper town, separate from the new cathedral of Sant'Agostino down in the valley. Access is through an atrium; the interior has a single nave with side chapels and a square choir. The cloister added on the right side in the late 15th century is reached from the church.

The bell tower attached to the left of the facade served as a model for other bell towers in the surrounding area. Inside, the chapel beneath the tower once held frescoes of the Stories of Saint John the Evangelist by Jacopo and Lorenzo Salimbeni, moved to the Pinacoteca comunale after the 1996 earthquake.