Ming-Tang, as an important Li-institution building, had a Ya-shape plan before Han dynasty, which originated from the universe mode of round sky with Ya-shape earth in ancient times.

明堂作为重要的礼制建筑，汉代以前平面为亚形，源自于上古时代天圆地亚形的宇宙观。

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Started during the Tang Dynasty and later expanded by Zhu Yuanzhang, the first Emperor of the Ming Dynasty (1368 to 1644), the stone wall extends more than 13.7km and is the most complete city fortification to have survived in China.

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