Vote here for worst episode...
My vote goes to the season finale, Episode 1x15: Hunt for the Holy Grail, although I haven't seen the whole series. Yes, the Holy Grail was definitely buried there, because Scott didn't find anything which proves someone must have moved it.
I'd hate to see this guy on a jury trial. He's the only person on the planet for whom the Chewbacca Defense actually MAKES SENSE (just YouTube it).
Before this show gets cancelled though, I WOULD like to see a crossover episode between America Unearthed and Ancient Aliens. Was it the Templars? Was it Ancient Aliens? Or was it Ancient Templar Aliens? Watch Scott and Giorgio battle it out for the honors of "Worst Logical Argument" and "Best Indiana Jones Outfit."