With kids, it depends on the day.
Come for the ramparts, not the rooms. The walk along the seaward walls gives a low, wide look straight down onto the working cruise port and the container cranes — a grittier, more industrial panorama than the postcard city views from Tibidabo or the Bunkers. The history is dark and specific: this fortress was turned on the city below it more than once, and Catalan president Lluís Companys was executed here in 1940 — a fact that still colours how locals feel about the hill. The catch: the interior is largely bare, so if you want exhibits rather than views and a heavy backstory, you'll be underwhelmed.