Castel dell'Ovo, Naples

Nice castle located almost in the sea. There is an interesting sort of beach next to which is really shallow and perfect for kids. However, keep in mind that the entry is free but you have to book it online. I don't know what's the point of this. Although it's free to enter, they won't let you in if you haven't booked online. I was really disappointed. Also, the castle is not very close to the city centre so you probably have to use transport.

A very picturesque seaside castle that is free to access and explore. Certainly worth a visit while in Napoli. You should sign up for a time slot in advance online. The process is fairly simple. The best part of the castle is it’s wonderful views. It has an enchanting feeling and the section with the cannons is very nostalgic. You can also do a guided tour for a small fee, which might be worthwhile, since you’ll probably be able to access portions of the castle that are restricted to general visitors.