Hi there, me and my girlfriend are 18 years old. I am planning a surprise holiday for her to go to Europe, for her birthday. We are both interested in museums, art galleries and seeing the famous sites of the world. I am planning to go during the summer season aswell. Any ideas on good places we can go? Would also be helpful if you can let me know of hotels and restaurants in the area aswell.

I look forward to hearing your answers to my somewhat, detailed, question!
Any answers are welcomed!
Thanks