Rome is a rare blend of the ancient and modern hardly found anywhere else in Europe. The number of historical sights and world famous artifacts is just astonishing for a single city. If you haven't visited Rome yet, you are missing a lot!
Istanbul is a mysterious city with long imperialist history where Eastern and Western cultures intertwine. The former great Constantinople offers the rare mixture of architectural styles that makes it one of the world's top tourist destinations.
If you, like the majority of people, think that Paris is the most beautiful city in Europe, you probably haven't been to Vienna. This is where the sublime meets neatness, and, most importantly, safety.