train from london to Holyhead then ferry to Dublin

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I went from Dublin (actually, Dun Laoghaire) to Holyhead... I live on an island, and this was the worst ferry ride I've ever been on. I much preferred the flight that I did from London to Dublin, as really there was no scenery on the ferry. If you're spending the time doing train, are you going to stay in Wales for a night or two? Otherwise, I'd just fly.

I've done the rail/ferry option many times from London when I was younger but its a real chore. If you've got visions of wind in your hair catching the sun on a 4 hour ferry ride and a pleasant roomy train ride with attractive scenery through the Welsh mountains and a coffee in your hand - the reality is just a grueling monotonous marathon grind. I went from your home town San Diego to San Francisco in one day last year by rail and that was much more pleasant.