Set in the 14th-century Cúria (a centre of judicial power), this small museum provides a fascinating window into Castelló's medieval history. You'll find stone carvings from the old Jewish quarter, a model of the once-walled medieval village, and an interactive exhibition on the era's troubadours. The highlight is the collection of creepy prison cells, complete with centuries-old graffiti at the end. An audioguide adds deeper insight into the whole experience.