Sand Mountain Introduction: The Saihan Bashang Plateau in northern Hebei Province is adjacent to the Hunshandake Desert in Inner Mongolia. Both the Big and Small Luan Rivers flow through the sandy areas of the Saihan Bashang Plateau. Changli County Chronicles record: The Luanhe River entered the sea from Baigezhuang (Tanghai County) before the second century. From the 12th to the 13th century, it was first brought into the sea through Xisha River and Tuanlin in Changli County, and then through Maohebei. The sand from the Bashang Plateau was washed by the Luanhe River for more than 800 kilometers and was gradually deposited in the shallow sea where Emerald Island is located. The ebb and flow of the sea and the northeast monsoon brought the sand to the coast. After hundreds of years of wind and tide, it gradually The accumulation formed today's ocean desert.