The route connects Eunpyeong-gu and Jungnang-gu in a U-shaped manner, running through Yongsan-gu and Seongbuk-gu.

It is mainly used to connect to the northern outskirts of Seoul and to relieve the traffic on other lines.

The line primarily operates in the section between Eungam and Sinnae, though some trains end one station before at Bonghwasan.

[1] However, it was not until March 2001 that the whole line was fully operational when the four stations from Itaewon to Yaksu were opened.

[3] In January 2013, the Seoul Metropolitan Rapid Transit Corporation, which operates this line, published free guidebooks in three languages: English, Japanese and Chinese (simplified and traditional), which features eight tours as well as recommendations for accommodations, restaurants and shopping centers.