The Great Wall

The Han Dynasty finished the Great Wall by extending it towards the Gobi Desert. This increase of the Great wall was considered the nicest contribution from the Han Dynasty. While extending the Great Wall there was a lack of materials so that they could continue, but the Chinese engineers found something to replace the material needed, while extending it. While extending it they used some of the things that Qin Dynasty did to build the Great Wall. Some of the ideas used from the Qin Dynasty was the way that they finished extending, because it involved putting down a layer of willow reeds, maybe even woven first, then on top of the 1st layer, a 2nd layer is put down. In the 2nd layer a little bit of water, and grave, were put together until it becomes solid. After the 2nd layer is put down, a new layer of gravel is added again. This would be repeated until the height wanted is reached. Some parts of the Great Wall is still standing mostly because of the dry climate of the Gobi Desert. Another thing that the Han Dynasty did was, that they improved was the watch over of the Great Wall, they also improved it by making it 2 stories tall so that you have a better look at everything.
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