Our family visited Momento park, and really enjoyed it. My children, who didn't know anything about Communism, were amazed by the statues -- their size and scale, as well as what they represented. But the high point of the trip was definitely the "how to be a spy" movie. Momento Park is definitely something to see when you're in Budapest, especially if you're curious about that time in Hungary (and all of Eastern Europe).
We managed to find the private bus stop at Deak Ter without much trouble, and the trip was surprisingly short. The park itself isn't that well labeled or laid out, though; we looked at the statues (reading the descriptions from the Rick Steves book, like so many other people), and then wondered what else there was to see, before discovering that there was a whole exhibit and movie outside and across the street from the sculpture park. My suggestion would be to start with the movie, and then move across the street to the sculptures. But this is definitely a place worth visiting.
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