"The pictures don't do this wonder of the world justice," Cohen says. "It's fascinating how the wall has many twists and turns and how the steps are deliberately uneven, perhaps to slow down invaders." This man-made structure, which stretches over 13,000 miles from east to west, was completed during the Ming dynasty and draws over 10 million visitors a year. That fact alone might deter a seasoned traveller. But even with the long lines and extra effort of trying to snap a photograph without other people wandering in and out of the shot, it's worthy of a visit. And don't wait too long - 30 percent of it has disappeared due to erosion and human interaction. A portion of the wall was even underwater - a result of man-made flooding - and only recently reappeared due to a drought. In other words, to be in the presence of such a massive architectural feat is something that every traveller should deem necessary.
