Possibly, Snapper. One might surmise that the preferred overnight places would be Westport, Galway, Limerick or Ennis, Killarney, Waterford, Cork, somewhere in or about Belfast, as well as (obviously) somewhere in Dublin.
I don't think the Dardanelles would cut it!
The serious question remains - which of these locations would be able to accommodate an overnight train with water supply, passenger access and so on; without contravening our excessive H & S regulations or compromising security?