| 6ROADS Observatory 2 | Nerpio | — |
| AAS Montsec observatory | Lérida | — |
| Ad Astra Sangos Observatory | Alhendín | — |
| Ager observatory | Ager | — |
 Ager observatory | Ager | — |
 Ager observatory, Lleida | Lérida | — |
| AGP GUAM 4 observatory | Málaga | — |
 Agrupación Astronómica de Sabadell | Sabadell | — |
| Albanyà Observatory | Albañá | — |
| Albireo Observatory | Inca | — |
| Albox observatory | San Roque | — |
| Alginet Observatory | Alginet | — |
| Alicante observatory | El Campello | — |
| Aljaraque Observatory | Aljaraque | — |
| Alnitak observatory | El Puerto de Santa María | — |
| Alt emporda Observatory | Urdanta | — |
| Alto Turia astronomical center | — | — |
| Amanecer de Arrakis observatory | Alcalá de Guadaíra | — |
| Ametlla del Valles observatory | Can Reixac (Sant Gregori) | — |
| Anunaki Observatory | Rivas-Vaciamadrid | — |
| Anysllum observatory | Ager | — |
| Aravaca Observatory | Madrid | — |
| Arcangel observatory | Las Zocas | — |
| Armilla observatory | esfera armilar | — |
| Arroyo Observatory | Miguel Arroyo Hurtado | — |
| ART observatory | Fregenal de la Sierra | — |
| Artemis Observatory | Parque Nacional del Teide | — |
| Asociacion Astronomica de Cartagena | Canteras | — |
| Astreo Observatory | Mairena del Aljarafe | — |
| AstroCamp observatory | Nerpio | — |
| Atlante observatory | Santa Cruz de Tenerife | — |
| ATLAS–TDO observatory | Tenerife | 2.370 m |
 Badalona Boreal observatory | Badalona | — |
| Badalona observatory | Badalona | — |
| Banyoles observatory | Bañolas | — |
| Berta observatory | Sabadell | — |
| Betera observatory | provincia de Valencia | — |
| Bilbao Observatory | Bilbao | — |
| Blanes observatory | Blanes | — |
| Blanquita observatory | Rivas-Vaciamadrid | — |
| Bootes Observatory | Boecillo | — |
| BOOTES-2 Observatory | Algarrobo | — |
| Burjassot Observatory | Burjasot | — |
| Busot observatory | Alicante | — |
| Caimari observatory | Caimari | — |
| Cala d'Hort observatory | Es Cubells | — |
| Calar Alto TNO Survey | Gérgal | — |
| Calar Alto-CASADO observatory | — | — |