Yalu River is named after the color of water. The green river is like the bright green around the neck of a male duck. The ancestors called it Yalu River, which has been passed down to this day. In the past, the Yalu River was called Mashui. Yalu River was called dam water in ancient times and water in Han Dynasty. The Tang Dynasty was called Yalu River, named after its green water like duck head. The Yalu River originates from the southern foot of Changbai Mountain in Jilin Province, flows through Changbai, Ji 'an, Kuandian, Dandong and other places, and flows southward into the Yellow Sea, with a total length of 795 kilometers. It is the boundary river between China and North Korea. The Yalu River flows through Dandong City for about 300 kilometers. This section of the river has a wide surface and beautiful scenery on both sides. In the estuary area, whitebait is abundant. The history of bridge construction in Yalu River is very early, dating back to Liao Dynasty. At the beginning of the 20th century, an iron bridge was built on the Yalu River, and two bridges were built between Dandong and Sinuiju, Korea. The first bridge was built at 1909, which is a retractable bridge. 1950 during the Korean war, it was bombed by American planes, and the pier still exists today. Now there is an end bridge tourist area. The Second Bridge, built in 1940, is a 940-meter-long railway-highway bridge jointly managed by China and North Korea. It is the traffic artery between China and North Korea, and it is also a tourist attraction for tourists.