The museum has some very interesting pieces, esp. medieval period weapons and armor, a large collection of cannons, and some firearms. It suffers from an obvious lack of funding (which is understandable since the admission price is 3eu). It seems like the museum is an afterthought of the Portuguese Military that runs it. If they had a professional museum director and staff with some money, this could be an amazing museum (like the Maritime Museum is, which is down the road and is superb). That said, it's well worth the 3 euros admission and has some cool stuff (the caricature figurine collection was a neat idea). It is lacking in more modern Portuguese military exhibits, outside of some uniforms. The weapons on display are quite limited. Given how much space they have and the long history of Portugal, there's a lot of unrealized potential.