planning to do a day trip from rome. taking early train, do the HOHO bus and have lunch and take train back evening on a monday in october. not interested in pompeii, anything else i should see and do there? it's to be a fun day. Thanx
You can check out the Naples Underground. There's also the National Archaeological Museum, but if you are not interested in Pompeii, it's possible that you also will not be interested in this museum (it houses a lot of the Pompeii artifacts).
I would suggest you keep an eye on the garbage problem in Naples. I just returned from Italy where there was almost daily news coverage of the situation. The images of huge piles of months-old garbage in the streets and people wearing scarves and handkerchiefs over their noses prompted us to take Naples off our itinerary for this trip. They are working hard to solve the problem, so perhaps by October it won't be an issue.