The itinerary lasts 15hrs 53min, and has 4 steps, and it will cost 71 euros minimum.

Dublin - Holyhead
The step from Dublin to Holyhead lasts 3hrs 15min. You'll travel in a ferry.
On board, you'll have access to: Drinks and snacks, Bike.
You can find tickets from 44 euros if you book 2 months in advance.

Holyhead - London
The step from Holyhead to London lasts 3hrs 50min. You'll travel in a long distance train.
On board, you'll have access to: Wi-Fi, Drinks and snacks, Bike.
You can find tickets from 27 euros if you book 2 months in advance.

London - Paris
The step from London to Paris lasts 2hrs 18min. You'll travel in a Eurostar.

Paris - Barcelone
The step from Paris to Barcelone lasts 6hrs 30min. You'll travel in a high speed train.