These geometric forms present one of the biggest unsolved mysteries in pre-historic exploration.

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Since he fled, Irving's profile has been featured on the TV shows "America's Most Wanted, " "Unsolved Mysteries" and "Real Stories of the Highway Patrol, " according to the Most Wanted poster.

CNN: Convicted rapist caught after nearly 35 years on run

If you like your mysteries unsolved, you can even take the Finnish tour.

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