My girlfriend and I visited Naples on a day trip from our base in Sorrento. Like everyone else has said it is incredibly dirty with bags of rubbish, litter and graffiti everywhere you look. We didn't feel safe walking around and there is a surprising lack of police around. Its a real shame as there is bags of potential for it to be great city, but its ruined by the high crime rate and filth. We visited the national archaeological museum which was a disappointment as around 50% of the exhibits were shut but what we did see was good and built on what we saw at Pompeii. Maybe if the city sorts its many social problems out it would be a great place to visit, but I certainly wont be going back anytime soon.