It is a very nice museum in my opinion, for a tourist interested in history (in this case, budapest history - this covers the local history since roman empire up to the communist days). This is comparable to the good museums I ever visited, with many rooms/floors and many things with good labels and audioguides to learn about. Located at the famous "budapest palace".
The funny thing (and weird one) is that, neither my tour company's guide nor our budapest local tour guide knew about this museum! I knew about, because I have one of those famous tourism books that I bought in Brazil (my homeland), so me and my wife went alone to this museum.
Otherwise, I would never visit that.
Due to this lack of guide's information about it, I thought I would get there and see something small and deteriorated. But I was glad it is the opposite.
My hint: I went in april-2013. By that time, they accepted neither Euro (cash) nor credit cards in the museum entrance, so be prepared and take some local currency (in cash) with you!
I can not rank it with a grade or something like that, because this depends on your background and expectation. What I can tell you is that the overall experience was very good for us.
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