Zephs 3'4" STL so I just didnt cage him. i didnt feed him either (for the three day trip) so he wouldnt poop in the truck or anything. This was July 03 from NH to FL in the front of a Uhaul truck. VERY crowded. I literally held on to Zeph for the majority of the trip. I set up some towels over a stack of suitcases and let him watch through the window. I still soaked him each night at the hotels (bring your own discenfectant/cleaner). If youre driving and there is nobody to watch/hold your iguana, and/or if hes a smaller, quicker iguana Id definitly secure him.
We got stopped by the Florida fish/game people as we crossed the GA/FL border because a spotter saw Zephyrs tail hanging near the window and mistook it for a snake.
Thats the only time weve traveled with him (except to the vets, or out and about locally) and he is already a calm iguana, he didnt give me any trouble.
Keep his stuff easily accessable (sp?) before,during, and after the trip...pay close attention to his health and appetite during/after too.
thats about all I can think of..traveling is stressful so just keep a good eye on your iguana.
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Sarah