Take a day to visit Europe's tallest active volcano, Mount Etna. The mountain is a UNESCO World Heritage Site for its natural and geological significance. Take a tour or hike up the mountain to see the scenic view of the city and its surroundings.
Spend the day exploring the ancient city of Syracuse, which was once a powerful city-state. Visit the Greek Theatre, the Archaeological Park and the Ear of Dionysus. Enjoy a seaside lunch in the Ortigia district, which is a charming island with small streets and alleys.
Finish the trip by relaxing on one of the most beautiful beaches of Taormina. Spend the day on the beach, sunbathing, and swimming in the crystal-clear waters. Take a walk in the town and enjoy the local cuisine of fresh seafood and pasta.
If you have more time, consider visiting the Valley of the Temples in Agrigento, an hour and 45 minutes from Catania. If you have less time, you can skip Syracuse and spend more time at Mount Etna or Taormina beach. Note that the Mount Etna tour is weather-dependent, so be sure to check the forecast before going.