The EU granted €530m to Eirgrid merely to plan the Celtic Interconnector, a 500km long electricity/fibre optic cable linking Ireland and France, or over a million per km just to pencil it out on the back of a Homosexual packet. What it will eventually cost to complete is unknown but naturally it will be casually spoken of in multiples of a billion. Just how many ferries could be run for the same money as a tunnel is going to cost probably runs into the hundreds or thousands, so why not just provide free shipping instead? It will be at the merest fraction of the cost.
Edit: Had to laugh, I wrote 'Fa g' packet which got changed to Homosexual by the system. Gonna leave it as it is!