大运河长江至淮河段最早开凿于春秋时期,时称邗沟。在唐宋以前,大运河江淮段由南向北流,经过数百年的演变,至明清时期改为由北向南流。大运河江淮段流向的逆转,既是“借黄济运”政策的必然后果,同时也反映了运河一线地势的重大变化。 The Grand Canal to the Huaihe River Yangtze River to the earliest cut in the Spring and Autumn Period, when called ditch ditch. Before the Tang and Song dynasties, the Grand Canal between the Yangtze River and the Huaihe River flows from south to north. After several hundred years of evolution, it changed from north to south in the Ming and Qing Dynasties. The reversal of the flow direction of the Grand Canal between the Yangtze River and the Huaihe River is both an inevitable consequence of the policy of “borrowing the Yellow Sea and transporting the economy,” but it also reflects major changes in the topography of the canal.