The Romanesque-Byzantine cathedral crowning Monte Guasco is Ancona's defining landmark, built from the 11th century on the site of a Roman temple. Its pink-and-white stone facade and cupola are visible from far out at sea. Inside, the nave is austere and cool; the crypt holds the remains of Saint Cyriacus, the city's patron. The hilltop position rewards the climb with panoramic views over the harbor and coastline in both directions. Entry is free.