The Great Wall at Mutianyu:
Complete wall, most watch towers on the shortest section, and fortified passes. This area is a reconstruction but done very well. Mutianyu is the most popular attraction in Beijing on Trip Advisor, and most recommend section with international travelers, guidebooks and travel bloggers. It is less crowed than Badaling and Juyongguan sections. Winding on the high mountains and lofty hills, the Mutianyu Section of the Great Wall features a great deal of historical, architectural, and military significance.
The Great Wall at Jinshanling:
An original section with a series of watchtowers and peculiar structures. The Great Wall at Jinshanling was first built in the North Qi Dynasty (550–557). You can still find the ruins of the wall from this period. This section of the Great Wall is situated on the ’Golden Mountains’. It is one of the best places for Great Wall hiking.
The Great Wall at Jiankou:
The most precipitous section of the Great Wall, wild, weathered and primitive. Jiankou is a "wild" (unrepaired) section of the Great Wall. It was built on ridges with steep cliffs on each side, which makes it one of the most dangerous sections. It's only recommended for experienced and sure-footed mountain hikers.