Map A is a picture of the Yuan Dynasty, the brown shaded area is the land ruled by the Yuan Dynasty. The thick green line is the border of the canal. The black dotted lines are the current borders of China and Mongolia. In map A Peking which is also known as Dadu was the capital during the Yuan Dynasty. In Map B Peking/Dadu is now Bejing the current capital of China. In map A and B the Pacific Ocean borders the Yuan Dynasty to the east. In map B North Korea is no longer a part of China and neither is Mongolia.