A rough and unsparing film.
From Arthur Huh
I acknowlege this is a difficult and impossibly loaded question, but to the extent you can answer it, literally, what would you say is the youngest age (in years) a person could be to watch "Hugo" in the the theater? And, by the way, if it helps, the reason I ask is, we are seriously (pretty much hell bent on) going to take our take our 4.5 year old daughter to see "Hugo."
Ebert: It contains no objectionable content. The film is complex enough for movie-loving adults, but quite accessible for bright kids. It may be that children below a certain age would find the sheer wonderment to be enough, coupled with the young ages of the two lively protagonists. The only problem might be the child's patience with a running time of slightly over two hours.