A tourist information desk, ready to answer questions and provide maps, lies close to the disembarkation point. [...] some friends I made on board my last Mediterranean cruise walked 100 yards off the ship, went through the terminal, and peered into Naples’ clogged streets. Had they kept on walking for 15 minutes (or caught a bus or taxi), they would have found themselves in a classic Neapolitan world … without a hint of tourism. Any traveler with good common sense will feel comfortable here — and will be richly rewarded for their adventurous spirit. If you arrive in the morning, a good first stop is the lively (and smelly) Porta Nolana fish market, which squirts and stinks as it has for centuries under a gate in the city wall, Porta Nolana, just in front of the Circumvesuviana commuter train station. Pop into a grocery shop and ask the owner to make you his best prosciutto-and-mozzarella sandwich (the price should be about $5). Wait for a break in traffic, and make eye contact with approaching drivers. Light a candle at one of Naples’ powerful houses of worship along this strip, such as the Baroque Cappella Sansevero chapel. Using traditional wood-burning ovens, Naples’ pizzerias bake just the right combination of tomatoes, mozzarella and fresh dough (soft and chewy, as opposed to Roman-style, which is thin and crispy). An average one-person pie (usually the only size available) costs $5 to $10; most places offer both takeout and eat-in, and pizza is often the only thing on the menu.