Kaesong-si, DPRK... population 309,440, and quite possibly the only city in the world whose main street has such a distinct beginning and end, as seen below.
Source:
www.flikr.com - samthe8th
Also home to Kijŏng-dong, population ZERO, which would win the award for most impressive skyline per population if it only had "city" status. However, I guess that it needs people to live in it before that can happen.
Source:
www.flikr.com - Chimay Bleue