The islands of the bay
Capri, Ischia and Procida: three islands very close together that are nothing alike.
The three islands in the bay of Naples lie a few miles from each other and are three different places. Capri is limestone, vertical and expensive. Ischia is volcanic, far larger, with thermal water and a life that carries on through the winter. Procida is tiny, made of tufa, and until recently nobody went there.
Capri
You land at Marina Grande and from there you go up: by funicular to the piazzetta, by bus to Anacapri, by chairlift to Monte Solaro, from which you see everything. The Faraglioni are looked at from the Gardens of Augustus or from the water, on the boat trip. A day is enough, as long as you start early: after ten the big ferries arrive and the island changes.
Ischia
Ischia is large enough to have six municipalities and real traffic. People come for the thermal springs, which are why the island lives twelve months a year, and for the beaches, of which there are more than on Capri. The Aragonese castle, on an islet joined by a bridge, is the thing to see if you see only one.
Procida

Four square kilometres, no monuments, and the fishing harbour of the Corricella with its houses each painted a different colour. It was Italian capital of culture in 2022 and more people go there now, but it remains the island where you can spend a day without a plan.