National observatories and planetariums                

Stara ZagoraNAO 'Yuriy Gagarin'
VarnaNAOP 'Nicholas Copernicus'
YambolNAOP Yambol
DimitrovgradNAOP 'Giordano Bruno'
ChepelareNAO 'Rozhen' at BAS
SilistraNAO 'Galileo Galilei'
SmolyanNAOP Smolyan
slivenНАО Сливен
KardzhaliNAO 'Slavey Zlatev'
GabrovoNAOP Gabrovo
BelogradchikNAO 'Belogradchik' at BAS
AvrenBase Astronomical Observatory at NAOP Varna
VarnaPlanetarium of the Higher Naval School "N. J. Vaptsarov"

Other astronomical observatories                

SofiaDepartment of Astronomy at the Faculty of Physics of Sofia University
SofiaChildren science center 'Muzeiko'
SofiaObservatory of the Astronomical Association - Sofia
HaskovoAstronomical Observatory at the Haskovo Youth Center
ShumenAstronomical Observatory - Shumen
ShumenAstronomical Center at the Shumen University
RozhenRemote Amateur Observatory 'IRIDA'
PlanaSofia University Student Astronomical Observatory
RozhenObservatory of association 'Stellar Society'

Astronomical organizations                

SofiaUnion of Astronomers in Bulgaria
SofiaInstitute of Astronomy at the Bulgarian Academy of Sciences
ShumenDepartment of Physics and Astronomy at Shumen University
SofiaDepartment of Astronomy at Sofia University
SofiaAstronomical Association Sofia
SofiaNational Astronomy Olympiad
SofiaSpace Research and Technology Institute

Astronomical clubs                

SofiaAmateur astronomers club "Stellar Society"
HaskovoAstro club 'Helios'
Stara ZagoraClub of amateur astronomers 'Gemma'
PeshteraAstro club 'Cor Caroli'
KardzhaliAstro club 'Vega'
Dolni ChiflikAstro club 'Perseus'
BajkalAstro club at Municipal Center for extracurricular activities in Dolna Mitropolia
TroyanAstronomy class at 'Vasil Levski' school
DimitrovgradAstro club 'Antares'

Astronomical equipment                

AndromedA Ltdwww.telescope.bg

General astronomical topics                

Introduction to astronomy and space explorationwww.homeadvisor.com/r/home-science-backyard-astronomy/
News and info for Earth-Sun systemwww.spaceweather.com
American GPS system web sitewww.gps.gov
Local information for astro eventsin-the-sky.org
Astro WIKI pagesbg.astronomy.wikia.com/wiki/Астроуики
Information about coming astronomical eventsfreestarcharts.com
Astronomy for amateurswww.astronomy4all.com

Astronomical software                

Modern program for designing and analysing optical systemswww.myoptics.at
PlaniSphere - online starmap in many languagesdrifted.in/planisphere-app/app/index.xhtml
Astro software cataloguewww.midnightkite.com/index.aspx?URL=Software
Program for occultations processing, Hristo Pavlovwww.hristopavlov.net/Tangra/Tangra.html
Program for controlling CCD and digital cameraswww.ideiki.com/astro/Default.aspx
Several applications for ephemeris calculation and other celestial eventswww.alcyone-ephemeris.info
Windows application for full observatory controlwww.omegalab-atc.com

Atmospheric conditions                

Detailed weather report with forecasts for the world 1www.windy.com
Detailed weather report with forecasts for the world 2www.meteoblue.com
Where the night is darkest 1darksitefinder.com
Where the night is darkest 2www.lightpollutionmap.info
Where the night is darkest 3mpetroff.net/files/light-pollution/
Where the night is darkest 4worldview.earthdata.nasa.gov