First, we didn't want to drive. To deal with parking, which is quite expensive, the cheapest parking available at any of the places we stayed, if offered, was 15 € per day, plus IVA. Then there is gas, and insurance, and speed limits, and can you right turn on red, what are the rules on passing, ack, no thanks!
And although I did snatch this foto off the web, we actually did drive right by the Guggenheim and got a really good view of it was we passed through, well around, Bilbao.
Or you can nap, or use their free wifi, use the aseo, get a beverage...
And you can get anywhere, it just takes a little work, and asking questions to figure out how to get from point A to point B, or C.
On three separate travel days, passing long distances we spent an average of 70€. We had quite a few non travel days, and most of our travel days were less than 10€.
So for us, it's planes, trains, and automobiles all the way, oh, and throw in some buses, taxis, a boat or two, and the Metro.
In fact, I am writing and posting this from our bus back to Madrid. Tomorrow is the long haul from Madrid via Amsterdam to Houston.