The Holyhead to Dublin ferry route is operated by 2 ferry companies, Irish Ferries and Stena Line providing a … Quickly book cheap Holyhead to Dublin ferries here with Ferrysavers. LARNE TO CAIRNRYAN FERRY The Larne to Cairnryan ferry route allows direct travel from Ireland to Scotland. The P&O Ferries service runs up to 7 times a day with a sailing duration of 2 hours. Compare ferries to England, France, Scotland, around Britain and more or less anywhere across the world with Ferry.ie.