My original thought was actually to push the JC out beyond the berm and have the DLRR tracks pass overhead sort of like they do in Tokyo. Problem is the tram loading area, the Indy show building and of course DCA all being in the way. That's what lead me to thinking about a show building about the size of POTCs inside the berm.
While going indoors has the advantage of a more controlled environment with more elaborate AAs and effects, I agree that the outdoor Jungle Cruise is a unique and wonderful experience.
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