'Around the city'
Napoli is a big city. One needs several days to walk around it's center. There are so many places to visit in the city and you will feel soon overwhelmed.
My advice is to stick only to the most important attractions of the city, otherwise you will end up stressed not being able to visit everything and exhausted.
Besides, the best attraction of a city is its people, its aromas and its colors, not the palazzi, the churches and the museums.