A stiff but scenic climb up from the old town, Ancona's domed cathedral dominates the city skyline. Guarded by two marble lions, it commands sweeping views from its perch atop the Colle Guasco (Guasco Hill), formerly the site of an ancient pagan temple. The church's origins date from the 6th century, but it took on much of its current form between the 12th and 13th centuries and today features an architectural potpourri of Byzantine, Romanesque and Gothic features.
Wandering downhill from the cathedral along Piazza Anfiteatro, you'll see the remains of the city's Roman amphitheatre, believed to have been built during the reign of Emperor Augustus.