Begun in the 12th century and not finished until the 17th century, the city's main church still boasts its original main doors and portal, magnificently covered with low reliefs in the Lombard Romanesque style that are attributed to Niccolo, whose work can be seen at the Basilica of San Zeno Maggiore. The church was built upon the ruins of an even more ancient paleo-Christian church dating from the late Roman Empire. Visit the Cappella Nichesola, the first chapel on the left, where Titian's serene but boldly colorful Assumption of the Virgin is the cathedral's principal treasure, with an architectural frame by Sansovino (who also designed the choir). Also of interest is the semicircular screen that separates the altar from the rest of the church, attributed to Sanmicheli. To its right rises the 14th-century tomb of Saint Agatha.
The excavations of Sant'Elena church, also in the Duomo complex, reveal a bit of 6th-century mosaic floor; the Baptistery contains a Romanesque font carved with scenes from the Nativity cycle.
Don't leave the area without walking behind the Duomo to the river: Here you'll find the 13th-century Torre di Alberto della Scala tower and nearby Ponte della Pietra bridge, the oldest Roman monument in Verona (1st c. B.C.; rebuilt in the 14th c.). There has been a crossing at this point of the river since Verona's days as a 1st-century Roman stronghold when the Teatro Romano was built on the river's northern banks and the Arena at its hub.