The Great Wall of the Han Dynasty (202BC-220AD) followed characteristics of the Qin Dynasty because they both built their walls based on local conditions, and they both used local materials (Travel Guide). Earth and stones were still popular building tools during this time period; construction type did not really change that much until the Ming Dynasty came along. For example, the area they worked in grew a lot of poplar, dogbane, red willow, and bulrush ("Great wall of China tour"). The branches of the plants were used as the base. The branches were covered with a layer of sun-dried mud bricks mixed with grit, and the layer above was smashed with bulrush ("Great wall of China tour"). The average thickness of the bulrush layer measured 1.6 …show more content…
The Ming received many disturbances from nearby minority tribes such as Dadan, Tufan, and Nuzhen, so the Ming court’s emperors emphasized the continued building of walls. The Ming portion of the Great Wall is the most complete and strongest structure of all of the other dynasties because the Ming dynasty took past experiences from the other dynasties and improved all of the problems they identified. Using bricks for majority of the building purposes were a major contribution to the wall. Bricks were more a convenient material than earth and stone as their small size and light weight made it better for workers to carry and ultimately quickened the speed of construction. Bricks were also the ideal material to bear the weight needed to support the wall. According to a sample experiment experiencing gravity and erosion over a hundred years, the brick’s compressive strength and resistance to freezing and absorbency during that time are similar to today's common bricks. A huge brick from a hundred years ago shows a high level of technological skill for that time period. To continue the ease of construction, different shapes of brick were also burned and made to insert into different places. Besides bricks, other changes were important factors as well, such as adding more military fortifications to the wall, creating big wide moats in the flat areas outside the wall to make intruder approach a lot more difficult, and creating terraces. Terraces are small areas that protrude from the wall, and it allowed soldiers to be active in close combat. Enemy soldiers have even camped right outside the wall, and they waited for their opportunity to strike and invade; however, the creation of the terraces allowed soldiers to stop their enemies’ plan. The terraces are a very useful advantage due to their height and location. Looking down on enemies always gives that side the upper hand in a battle. Soldiers on the wall