My favorite mode of transportation while traveling is using Public Transportation. I enjoy taking trains, ferry’s, buses, etc. Here a collection of helpful links I’ve used:
SCOTLAND – ScotRail
ITALY – Trenitalia
NETHERLANDS AND BELGIUM – Thalys
SPAIN – Renfe
GERMANY – DB Bahn
The Man in Seat Sixty-One – This is a great site to learn about Train Travels in Europe.