Original sentence: It is based on the ruins of Hwando Fortress that served as the second capital of Goguryeo (Chinese: 高句麗；Pinyin: Gaogouli).Wandu Mountain City (Chinese: 丸都山城) is a UNESCO World Heritage Site located in 2.5 kilometers to the west of Ji'an, Jilin, China
Edited sentence: It is located in 2.5 kilometers to the west of Ji'an, Jilin, China.It was the fortress of the capital "Guonei City", then also became the capital city at year 209.Wandu Mountain City (Chinese: 丸都山城; Korean: Hwando fortress), along with Guonei City (Korean:Guknae Seong), served as the second capital of Goguryeo (Chinese: 高句麗；Pinyin: Gaogouli)