Hanhai (hà n hƺ i) is a Chinese word. Originally refers to the sea, that is, the great lakes in the north, and later refers to swamps, vast areas in the north, and Gobi desert.

　　Explain in detail:

　　(1). Place names. Its meaning changes with the times. Or it is now Hulun Lake and Bell Lake, or it is now Baikal Lake, or it is translated as the voice of Hangzhou Aishan. The Tang Dynasty is a general term for the vast area north of the great desert in the Mongolian Plateau and its west to the present Junggar Basin. It is also often used as an allusion to campaigns and martial arts.

　　Historical Records Biography of General Wei's title of generals in ancient times: "(Huo Qubing) sealed the wolf to live in Xushan, meditated in Guyan, and boarded the vast sea." In the Southern Dynasties, Liang Yuxi's "General Yong Huo's Northern Expedition": "Flying foxes are at night, and the sea is gloomy." Tang Gaoshi's Yan Ge Xing: "till their captains over the Sea of Sand were twanging feathered orders, the Tartar chieftain's hunting-fires glimmered along Wolf Mountain."

　　(2) refers to the desert.

　　Tang Taohan's poem "Going out to Xiao Guan to remember the past" reads: "The lonely city is a vast sea, and the sun sets in Qilian." Ming Zhao Zhenyuan's "Sacrifice to Yuan Shiyu (Yuan Keli's son) Xian Fu": "The falling rhyme flies to Britain, and the sky surprises the rain. Waving and waving, cranes are born with wind. The vast sea is famous, and the poetry world listens to jade. " Zheng Guanying's "On the Post in the Prosperous Age": "Yuan Xianzong is in the middle of the vast sea and has set up checkpoints along the way." Chen Yi's "The Great Wall Ci": "The revolution is really ingenious, and the people of all ethnic groups are United, and the vast Gobi will become a treasure."

　　(3) The name of Tang Duhu. In Zhenguan, the mansion of DuDu in Hanhai belongs to Anbei DuHu. Longshuo changed its name from Yan 'an DuDu House to Hanhai DuHu House.