How dark is the sky in Latvia?
Sky darkness for 28 towns and parks in Latvia, worked out from NASA satellite images of light at night (2025). 18 of them have skies of Bortle 4 or darker, where the Milky Way shows overhead. The darkest is Slītere National Park (21.83, Bortle 3), the brightest Riga (17.72, Bortle 8).
19
Bortle class, 1 pristine to 9 city center
park or dark-sky place
city
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 Latvia
- Slītere National ParkKurzeme · Bortle 321.83
- Rāzna National ParkLatgale · Bortle 321.80
- Istra Hills Nature ParkLatgale · Bortle 321.78
- Sauka Nature ParkZemgale · Bortle 321.76
- Užava Nature ParkKurzeme · Bortle 321.74
Among the places on this site. Plenty of land between them is just as dark, with no town or park to name it by.
Darkest place in each region of Latvia
| Region | Places | Dark places Bortle 1 to 4 | Darkest place |
|---|---|---|---|
| Kurzeme | 10 places | 8 dark | Slītere National Park21.83 · Bortle 3 |
| Latgale | 4 places | 2 dark | Rāzna National Park21.80 · Bortle 3 |
| Riga Region | 2 places | 0 dark | Jūrmala19.59 · Bortle 5 |
| Vidzeme | 7 places | 5 dark | Gaiziņkalns Nature Park21.72 · Bortle 3 |
| Zemgale | 5 places | 3 dark | Sauka Nature Park21.76 · Bortle 3 |