If you might be looking for longer trips round Ireland to explore various areas, you might contemplate checking out the excursions from Dublin provided by Rabbie’s Travel. There are regular ferries from Cairnryan, Scotland to Larne / Belfast in Northern Ireland. The two major ferry corporations are Stena Line and P&O Ferries. It is feasible to go to Edinburgh as a day trip from London, however actually, we would advise against this.