Bloody loved the Crystal Maze when I was a kid. Used to dream of getting on the children's special they'd do once a year.
Futuristic zone was the nuts, never too keen on the Aztec zone. Honorable mention to the zone that was a bit like a sinking ship that they brought in half way through.
Ocean.
It was set aboard the SS Atlantis, which has sunk to the bottom of the sea but had rather remarkably avoided taking on water in some areas.
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