This place is amazing. So much history can be felt when inside. We stayed for a quite a while enjoying views of the city, and of the ocean.
A beautiful stunning overview over Barcelona, the way to the castele is not family friendly with a trolly it is not easy accessable
I took a bumpy cable car ride up to the castle where I was given an option to have my harassed looking self take a picture which I did then made my way to the castle ticket booth bought my ticket & strolled in. The castle had many restricted areas but there was a temporary exhibition- montjuic prison and memory of Barcelona showing how the castle had been used over time. Then it had the open courts to walk around in & take loads of selfies. There were paranomic views of the sea/port & the city. Besides that nothing much to do up there.
One the best point of view of the city and the port, at only 2' minutes by metro and funicular, as also very access by foot in 30 minutes.