Make the most of your time in Belfast's port with a day-trip along the coast of Northern Ireland. Journey along the Causeway Coast, known for its coastal cliffs, exquisite views, and unique geological formations, which include the famed Giant's Causeway. Afterward, head for the precariously perched ruins of Dunluce Castle, and learning about its tumultuous past, before returning to Belfast for a bit of sightseeing before re-boarding your cruise ship.