Before I talk about this great castle, I want to say that I suggest you not eat in the small cafeteria. I saw first hand a kitchen staff go straight from washroom to kitchen prep without washing hands. I'm going to leave it at that but it made me feel sick knowing what he did in the washroom and then casually return to food. Go down into the town to eat.
Aside from that insignificant detail, this is one of the most enjoyable castle visits we've had. Tons of history, great views, plenty of attention paid to improve experience for younger visitors, clean (except cafeteria) and well maintained. There were some auxilliary exhibits unrelated to the castle but really interesting, nonetheless. If you're on Jersey, this castle well worth the visit. Easy access by bus from St. Helier.
This review is the subjective opinion of a TripAdvisor member and not of TripAdvisor LLC.