Big islands among them are Anjwado (45.2 km2), Aphaedo (44.3 km2), Bigeumdo (43.1 km2), Dochodo (40.3 km2), Imjado (43.2 km2), Amtaedo (38.7 km2), Jeungdo (37.2 km2), Jangsando (24.3 km2), Haui-do (16.1 km2), and Heuksando (19.7 km2).

The sea area is a continental shelf with less than 15 meter in depth.

[2] Sinan County is known for its specialities: Skate (fish) and Cheonilyeom (천일염, a Korean type of sea salt).

The more notable cases included the slavery on salt farms in Sinan County in 2014 and the Sinan County parents raping teacher case [ko] in 2016.

[3][4][5] Sinan County has two eup (읍) and twelve myeon (면).