After laying the concept art into the plans, you get the below give or take. The Potter and Monsters may be off a hair due to the art getting ambiguous and the presence of other buildings. But the Nintendo and Dreamworks areas are more defined and you can see the in-roads in the art and match them up. Seeing that, either what people are calling the HTTYD is a comprehensive Dreamworks area, or they are giving HTTYD more land than Mario and Donkey Kong combined. By a lot. As much as I'd like to see some of the meltdowns on here from that, I can't see them doing that.
Alternate take: the art is a complete lie and the lands aren't actually located where they show in the art.
Extremely accurate reproduction of concept art.... :
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