Florence to Sorrento in Mid March

For #6: According to publication information, the next edition will be available in December 2019.

1. In the bowels of the Naples train station (Napoli Centrale) there is a Circumvesuviana station. You follow the signs there, buy tickets and take that train to Sorrento. The trains run once or twice an hour, depending on the time of day, and the journey takes 1.25 hours or maybe a little more. This is called a train but it's really a metro, with frequent stops. Get used to it, that is what you'll use to get to Pompeii, Herculaneum and Naples for day trips. The buses to the Amalfi Coast leave from the train station. You'll read reports that this train is unsafe (thieves) but if you are seasoned travelers, it will be fine, especially in March when there are few tourist crowds. It may be convenient to take a taxi from the train when you first arrive.

2. The train station is a short (5-10 min) walk uphill from the town center. the sea shore is down a steep cliff. There are flights of stairs straight down and there are buses that take a circuitous route. There are also elevators that cost a couple euros each time, but they only operate in tourist season, so they may not be working yet in March. If you stay in the center, you'll be able to walk to/from the train for your day trips and you'll have a choice of shops (stuff is interesting, some local products) and restaurants.

3. There are always ferries to Capri and to Naples, though they can't sail in rough weather. Ferries to the Amalfi Coast usually begin in April.

4. I would recommend a day on the AC by bus. If the ferries have started, you could take the bus one way and the ferry the other. The best of the AC is the scenery. The towns are meh.

5. I would allow a full day for Pompeii - it's extensive and the long walk to the Villa dei Misteri is worth it. I would not bother walking out to the amphitheatre. There's a cafe in the park where you can get lunch and drinks. A half day is enough for Herculaneum (leaving you time to explore Sorrento). AFAIK there's no cafe, just a souvenir shop that probably sells drinks and snacks. I took a picnic lunch. Herculaneum can be visited in the rain, I would not try to see Pompeii in the rain though. Naples is worth a day. There are directions in the RS guide to get from the train station to the arch. museum by metro. Allow at least 2 hours. The guide also has a city walking tour that begins across the street from the museum.

I meant to add - google "circumvesuviana" to find train schedules. SITA is the bus company. Google it for schedules. The summer schedules are up now, not sure if you can find the winter ones yet. There may be fewer trains and buses in winter. There's one train line between Naples and Sorrento (the end of the line). In tourist season there are a few Campania Express trains as well, maybe not yet in March. There are two bus lines, Sorrento to Amalfi and Amalfi to Salerno. The ride from Amalfi to Salerno is the most scenic part of the coast.

Thanks to you for this precise, insightful and detailed info. This is just what I'd hoped for. Very grateful you took the time.

Wendy, just to add to Chani's excellent post, you can acquire a lot of info about Sorrento (getting around and whatnot) from this website:

https://www.sorrentoinsider.com

I would personally just ignore a lot of the touting for tours as it's a pretty easy region to get around on one's own so you don't really need them. The one exception might be for Pompeii? It's not difficult at all to get to (Circumvesuviana train) but it's a sprawling, complex excavation that can benefit from a guide if not up to do a lot of reading, which is how we did it.

I will second Chani's advice to stay near the center of town: that's going to put you closest to many of the restaurants, good strolling areas and train station. Consider Piazza Tasso Sorrento's center. And as she said, in mid-March ferries are unlikely be running yet along the coast from Sorrento with the exception of to/from Naples and Capri, if weather permits. Current ferry schedules are here: check them closer to your date of travel.

https://www.naplesbayferry.com/en/index

There are a few hotels in the town center area that have rooms with views of the bay. They tend to be pricy but, if off-season rates are in effect during late March, they could be affordable. It's worth checking.