Night Light of Héliopolis (Guelma) from space (Algeria) Src. Average luminocity for 10x10km area is 41.2436% and for 50x50km: 7.2882%.
Square area 10x10 km:
 5.49%
 7.33%
 8.24%
 4.76%
 4.21%
 3.3%
 7.69%
 8.24%
 10.99%
 30.04%
 9.71%Square area 50x50 km:
 0.53%
 1.14%
 1.09%
 0.82%
 0.63%
 0.71%
 1.09%
 1.79%
 1.46%
 4.73%
 86.02%Clear (daylight) street map image can be seen on geolist.org.
Map coordinates:
37° 4' 0.2" North, 6° 44' 22.7" East
36° 30' 13" North, 7° 26' 34" East
35° 56' 10.9" North, 8° 8' 45.2" East
Some cities around Héliopolis sort by population:
• Guelma
		4.8 km =3 mi, 
197°
• Azzaba
		39.9 km =24.8 mi, 
311°
• Besbes
		42.3 km =26.3 mi, 
58°
• Drean
		34.1 km =21.2 mi, 
53°
• Sedrata
		42.5 km =26.4 mi, 
168°
• El Hadjar
		42.4 km =26.3 mi, 
38°
• Boumahra Ahmed
		8.1 km =5 mi, 
128°
• Berrahal
		36.9 km =22.9 mi, 
1°
Sources (retrieved 2019-11-25):
» Earth at Night: Flat Maps 2012, 2016