The terrain is relatively gentle, with low mountains in the west and plains to the south and east.

There are several islands offshore, including Unmudo and Hyesŏngdo.

The climate is slightly wetter than average for North Korea, with an annual rainfall of 1230 mm.

In addition, Unjŏn leads the province in fruit production.

The P'yŏngŭi Line of the Korean State Railway, running between Sinŭiju and P'yŏngyang, passes through Unjŏn county.