Night Light of Ganghwa-gun (Incheon) from space (South Korea) Src. Average luminocity for 10x10km area is 50.5935% and for 50x50km: 28.7119%.
Square area 10x10 km:
 0.51%
 0.51% 7.82%
 7.82% 4.93%
 4.93% 11.39%
 11.39% 7.31%
 7.31% 15.31%
 15.31% 14.46%
 14.46% 16.33%
 16.33% 17.86%
 17.86% 4.08%
 4.08% 0%
 0%Square area 50x50 km:
 4.88%
 4.88% 5.18%
 5.18% 4.25%
 4.25% 4.56%
 4.56% 4.24%
 4.24% 5.23%
 5.23% 3.88%
 3.88% 3.96%
 3.96% 5.5%
 5.5% 8.44%
 8.44% 49.88%
 49.88%Clear (daylight) street map image can be seen on geolist.org.
Map coordinates:
38° 18' 4" North, 125° 46' 56.8" East
37° 44' 50" North, 126° 29' 8" East
37° 11' 21" North, 127° 11' 19.3" East
Some cities around Ganghwa-gun sort by population:
• Seoul
		47.8 km =29.7 mi,  114°
114°
• Incheon
		37.7 km =23.4 mi,  149°
149°
• Goyang-si
		32.4 km =20.1 mi,  108°
108°
• Bucheon-si
		38.1 km =23.7 mi,  136°
136°
• Kwangmyŏng
		45 km =28 mi,  131°
131°
• Kaesŏng, KP
		25.6 km =15.9 mi,  13°
13°
• Munsan
		29.1 km =18.1 mi,  64°
64°
• Yŏnan-ŭp, KP
		33.7 km =20.9 mi,  302°
302°
Sources (retrieved 2019-11-25):
» Earth at Night: Flat Maps 2012, 2016