How dark is the sky in Fribourg?
Sky darkness for 2 towns and parks in Fribourg, worked out from NASA satellite images of light at night (2025). None of them have skies of Bortle 4 or darker, where the Milky Way shows overhead. The darkest is Bulle (20.45, Bortle 5), the brightest Fribourg (20.05, Bortle 5). Milky Way season in Fribourg runs May to July: on moonless nights the bright core stands clear of the horizon, climbing to about 14° at its highest.
Numbers like 21.95 or 16.97 are the brightness of the sky overhead on a clear, moonless night, in mag/arcsec². The scale runs backwards: a lower number means a brighter sky, from about 22 for a natural sky to about 17 in a city center.
How the readings are made
Darkest skies in Fribourg
Among the places on this site. Plenty of land between them is just as dark, with no town or park to name it by.
