Just north of Beijing, you'll find one of the most famous monuments in the world: the Great Wall of China ... You can start hiking the Badaling portion at 6:40 a.m., and you must be down by ...

If you want a more organized trip, you can book a tour through a company like Great Wall Hiking that takes you to the Gubeikou and Jinshanling sections and to the West-Five-Eye Watchtower.