It is indeed a landmark of the city.
However, the best views & photo shoot are from the outside.
You can also view the castle from the inside but there is very little to see: a couple of rooms with preserved remains from various part of Puglia and a video narrating the history. Unfortunately, there one can't climb up the towers and similar castle like touring.
Nonetheless, the entrance fee is just 3 euro ... basically nothing. COnsidering the price, I would go inside from a rapid view.
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