How dark is the sky in Łódź?

Sky darkness for 10 towns and parks in Łódź, worked out from NASA satellite images of light at night (2025). 4 of them have skies of Bortle 4 or darker, where the Milky Way shows overhead. The darkest is Warta-Widawka Landscape Park (21.13, Bortle 4), the brightest Łódź (18.16, Bortle 8). The bright core of the Milky Way never climbs clear of the horizon haze anywhere in Łódź while the sky is fully dark; the rest of the band passes overhead, with the longest moonless nights from September to March.