Badaling has been heavily restored and is the most heavily touristed section of the Great Wall, but it is so majestic that it is a must see. The surrounding terrain is magnificent and breathtaking, and the wall clings to its form at impossible angles. Go on a weekday if you can to minimize the crowds. The wall is so huge, however, that if you walk far enough you can get a section of wall more or less to yourself. If you can manage that, you'll be transported back 500 years! Only about 50 miles outside of Beijing, it is more than worth the bus ride. It gets windy up there - bring a jacket.