Syracuse is a large site to visit. There is the archaeoligical park with the ruins of a large Greek theater, a Roman amphitheater, and a huge altar of sacrifice. In the oldest section of Ortygia you can see nice examples of Gothic architecture (houses and churches), Greek remains, and views of the sea. One of the most interesting sights is the main cathedral. At the front it has an 18th century facade put on after a devastating earthquake, but walk to the side and you see the archaic columns in the walls. This church was built within a large ancient Greek temple and many of the portions of the temple are still visible. A really remarkable place to visit. Along the shoreline of Syracuse you will see rocks with square cuts in them, a source of the stone used to make the ancient buidlings. Other quarries exist inland. These served as prisons of the Athenians captured during their attack on the city. In the quarry by the Villa Politi you can see the beginnings of the sculpture of a Greek column. Something not often mentioned is that Syracuse has Christian catacombs. A visit to them is quite the experience. Don't go too far from your guide because it is really easy to get lost!