I have stayed there three times. And all the rooms were safe. Actually there are no ghosts on the Queen Mary or anywhere else for that matter. It's all hype.
I'm not sure when it was built. But I went for Halloween "fright night" it was a treat. I have heard about the hauntings and there were "shadows" in every corner, unexplained movements, maybe my imagination.... Up to your trip to find out for you. They do have tours all year-round they even have a restaurant.
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