The most remarkable of all the attractions in Bergamo is the city's main shrine, the cathedral, which towers over the small Duomo Square (Piazza Duomo). No one knows exactly when the official residence of the Bishop of Bergamo was built, so the foundation date is considered to be the memorable day of August 18, 1697. On this day, Pope Innocent XI finally confirmed the cathedral status of the ancient Basilica of St. Vincent and consecrated it in honor of St. Alexander of Bergamo, the patron saint of the city.

History does not record in its annals how old the Basilica of St. Vincent was. It is only known that it was built no later than the 9th century and was one of the city's two cathedrals. The first ancient Cathedral of St. Alexander was destroyed in the 16th century, and the restoration of the Basilica of St. Vincent began under the guidance of the Italian architect Carlo Fontana at the end of the 17th century. The cathedral acquired its final appearance with a neoclassical facade, which is still preserved, during the last restoration in the 19th century.

The cathedral has the shape of a Latin cross and a huge high dome, crowned with a statue of St. Alexander of Bergamo (1851). More than a century later, the statue was covered with gold leaf. This unique statue can still be seen today. Even though the facade of the cathedral is almost hidden in the shadow of the magnificent basilica, its slender snow-white columns and statues of saints are visible from any part of the square. But even their unsurpassed beauty can not be compared with the luxurious interior of the cathedral.

Inside, Bergamo Cathedral is decorated with murals from the Basilica of St. Vincent. The carved wooden choirs by the famous sculptor and woodcarver Andrea Fantoni appeared later, in the 17th century. The main treasures of the cathedral are three ancient organs, some of the most outstanding organs in Italy.