The Great Wall of China is an assemblage of smaller walls built by various dynasties over many years. Builders erected these walls for protection from invasions by those from the north. The Great Wall itself, with a history lasting over 2000 years, measures approximately 8,800 km (5,500 miles) in length, although some of the sections lie in ruin or have disappeared altogether. It is the longest man-made structure in the world.

In the 7th century B.C., the first of the smaller walls were constructed. Few of these remain today, but they were the starting point of what became the Great Wall of China. The first emperor to have the various lengths of walls joined together was Qin Shi Huang, whose dynasty ran from 221-206 B.C. He is well-known for his Terracotta Army. From 206 B.C-1368 A.D., the Great Wall was extended and rebuilt in order to keep invaders from crossing the northern borders. During the Ming Dynasty, which ran from 1368-1644, the wall reached its greatest length. For the next three centuries, the Chinese abandoned the Wall. It was not until the late 20th century that some areas of the Great Wall of China were renovated and the well-maintained sections became popular with tourists.

Up until the Ming Dynasty, builders used rammed earth, adobe and stone to build the wall, but after this Dynasty, they used bricks. It was during this time that the Chinese invented the wheelbarrow and made great use of it when constructing the Wall. As Mongol raids continued periodically over the years, the Ming devoted considerable resources to repair and reinforce the walls. Sections near the Ming capital of Beijing were especially strong.

There are several sections of the Great Wall of China that visitors find interesting. Badaling is the most popular section of the wall. It is close to Beijing and easy to access and climb. There are shopping and dining areas as well as a hotel nearby. It is tradition that at this section travelers attach an engraved padlock to a chain that runs along the parapets.

For those who wish to explore without many tourists surrounding them, The Nan Pass, at the southern part of the Juyongguan section, is for them. It is known for its Cloud Platform, built during the Yuan Dynasty. This watchtower is made of white marble, with Buddhist writings and statues of gods on either side of the doorway.

About 70 km (45 miles) from Beijing is the Mutianyu section of the Great Wall. Although it is older than some of the other passes are, it looks nearly the same as it did centuries ago. It is known for its large number of watchtowers. In this one and one-half mile section, there are more than 20 towers, with three of them connected by a tunnel inside the wall. Those who do not enjoy going through tunnels may enjoy using the overhead cable car to view the beautiful scenery.

Viewing the Shanhaiguan Pass section of the Great Wall gives visitors a chance to understand the military power of ancient China. There are several tourist spots in this area such as the First Pass under Heavens. Because this was a defensive section of the Great Wall, builders constructed it with a stone base and a brick wall. Even today, this area is very strong. The nearby Great Wall Museum, which has a display of the history of the pass as well as military relics, is available for those desiring more information on the area.