There is a story (perhaps apocryphal) that up until the early 80's the Grand Mufti of Saudi Arabia, Sheikh Abdulaziz Bin Baz, insisted that the earth was flat. According to the story, he only changed his mind after Prince Sultan bin Salman, the first (and only) astronaut prince flew on a NASA mission in 1985. Upon the prince's return, he told the Grand Mufti that he had seen the earth from space, and it was in fact quite round. Well, confronted with a firsthand account from a member of the House of Saud, what could Bin Baz do but change his ruling.
Now, when geologists and historians tell me that most of the Arabian Peninsula was once underwater, I do believe them. But let's just say that after finding seashells and sharks teeth scattered about in the middle of the desert, I now believe them even more than before. Sometimes you just really want to see, and hold, the physical proof for something to really seem true.