Time negotiating the turn out of Sausmarez Park to the main road caused the delay.
The Supertrooper Ride has wowed the crowds at the North Show for the past two days.
Show committee vice president Josh Cotran-Gabriel says the attraction's owners had spent most of last night dissembling the ride and putting it on transporters.
But he says a delay caused the ride and crew, along with two other articulated trailers, to leave Sausmarez Park late.
"They were were supposed to leave at 4am but they were busy packing things away and didn't leave until 6am and unfortunately leaving later meant it hit the rush hour."
"It got stuck on the the way in so they knew it would get stuck on the way out, it wasn't unplanned."
"They knew it was going to and they know how to get it out, but it takes 90 minutes to do it safely, without damaging anything."
The trailers blocked the main road, the Route de Cobo, for more than an hour this morning.
The convoy made its way to St Peter Port but arrived after check in and so have missed the ferry.
The three articulated vehicles are now parked alongside the East Arm while plans are made to get them back to the UK.
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