Culture Talk

Rate my itinerary: 4 cities in 5 days by train, is this crazy?

Ok so for summer I plan Lisbon, Porto, then train to Madrid, then Barcelona. 5 days. I am architect so I want to see buildings in every city, maybe 2 museums each.

My friends say I am crazy and I will see only train windows. Be honest, 1 to 10, how bad is it?