Answer:
The boundary walls constructed by several dynasties had numerous courses. They range from Liaodong in the east to Lop Lake in the west, from the current Sino-Russian border in the north to the Tao River in the south, in an arc that approximately delineates the boundary of the Mongolian steppe, totaling over. Today, the Great Wall's defense structure is widely regarded as one of the most spectacular architectural marvels in history.
Step-by-step explanation: