I will be spending September through mid November 2014 backpacking around Europe. I plan to fly into and start my adventure in Amsterdam. I will be using eurail and easyjet flights from particular stops on my list depending on price and availability. I will also be staying in hostels as I will be 24 during the time of my trip. I love to be active so I would love to experience all I can while traveling include city bike rides or anything along those lines. Also, I am from the US and have never been to Europe before since I was 1 years old and born in Germany.
Here is my route: Amsterdam-Brussels-Luxembourg-Munich-Salzburg-Prague-Berlin-Krakow-Budapest-Venice-Florence-Rome-Naples-Siciliy-Monanco-Nice-Marseille-Barcelona-Granada-Seville-Madrid-Lisbon-Bordeaux-Pairs-London-Amsterdam.
My question for all of you: which of those cities should I skip? Are there any I need to replace with better options in surrounding areas? What are some of the need to see/do things in those cities?