Most of the county consists of Pidansŏm, an island in the estuary of the Yalu River.

Lying in the northwest corner of North Korea, Sindo borders the People's Republic of China to the north and west, and faces the Yellow Sea to the south; to the east, it looks across a narrow expanse of sea at Ryongch'ŏn.

Sindo county is divided into 1 ŭp (town), 2 rodongjagu (workers' districts) and 1 ri (village): Reeds are the chief local crop, but fisheries and farming also play an important role in the local economy.

[2] In 2011, China and North Korea agreed to develop Hwangkumpyong as a special economic zone, though the project stalled following the execution of Jang Song-thaek in 2013.

However, there is a bus connecting central Sindo to Pidan Harbour, and boats provide transportation to Sinŭiju and nearby Ryongamp'o workers' districts.