Nestled in the historic heart of Mainz is St. Martin’s Cathedral, a 1000-year-old cathedral that serves as the episcopal see of the Bishop of Mainz. Its soaring towers dominate the pedestrianized Old Town's half-timbered houses, and it represents the high point of Romanesque cathedral architecture in Germany.

The Cathedral of Mainz was first established in 975AD but continually restored and rebuilt over successive centuries. Much of its present form dates to the 13th and 14th centuries, with the cathedral surviving largely unscathed during the Allied bombing of Mainz during World War II. It was here that the Holy Roman Emperor Frederick Barbarossa took up the Cross in the Third Crusade, which was called by Pope Gregory VIII in 1188 to conquer the Holy Land from Muslim leader Saladin.

Witness the supporting pillars along the nave aisle decorated with statues of French and German saints, then admire the combination of Romanesque and Baroque architectural styles employed in the main dome. The cathedral crypt houses a contemporary gold reliquary of the saints of Mainz, with rococo choir stalls and a 14th-century pewter baptismal font highlights of the sanctuary.

The cathedral also houses the Diocesan Museum, which boasts an impressive collection of sacred art that spans a thousand years. Of particular note are the medieval sculptures and works by the Master of Naumburg and beautifully decorated reliquaries. In addition to its religious artworks, tombs belonging to powerful Electoral Prince Archbishops of the diocese are also contained within the cathedral.