The Cathedral of Saint Catherine of Alexandria, designed in the Bramante style, was built at the end of the 16th century at the initiative of Bishop Giovanni Andrea Caligari, who envisioned an imposing building for the city.

Completed in 1601, the cathedral is laid out with three spacious naves, separated by Ionic-style columns that lend harmony and lightness to the overall structure.

The high altar is dominated by the altarpiece depicting the Mystical Marriage of Saint Catherine, painted by Giuseppe Marchetti (1722–1801), an artist active in the 18th century.

Among the cathedral’s most important works are also The Madonna Enthroned with Saints Peter and Paul by Francesco Longhi (1544–1618), a painter of the late 16th century, and Saint Charles Borromeo in Prayer by Felice Cignani (1660–1724). In the chapel to the right of the high altar, there is an imposing wooden Crucifix of German origin, dating to the late 16th century. Tradition holds that it was donated by a pilgrim as a sign of gratitude for the hospitality received in Bertinoro.