Explore the dizzying heights of Simatai Great Wall

Clinging precariously to a ridge in the Yan Mountains, the Simatai section of the Great Wall on the outskirts of Beijing is renowned for its steepness. The section was originally built during the Northern Qi Dynasty (550-577) and rebuilt during the Ming Dynasty (1368-1644). It guards access to Gubeikou, a major strategic pass on the route to the ancient capital of Beijing.