100-199
- 100: Ähtäri, Finland
- 101: Kharkov, Ukraine (Astronomical Observatory of Kharkov National University, Астрономiчна обсерваторiя Харкiвського нацiонального унiверситету, a.k.a. ХАО, Харкiвська астрономiчна обсерваторiя)
- 102: Zvenigorod, Russia
- 103: Ljubljana, Slovenia
- 104: San Marcello Pistoiese, Italy (Osservatorio Astronomico della Montagna Pistoiese, Pistoia Mountains Astronomical Observatory; a.k.a. Osservatorio di Pian dei Termini, Pian dei Termini Observatory)
- 105: Moscow, Russia
- 106: Črni Vrh Observatory, Slovenia (Observatorij Črni Vrh)
- 107: Cavezzo, Italy (Osservatorio Astronomico "Geminiamo Montanari")
- 108: Montelupo, Italy (Osservatorio di Montelupo)
- 109: Algiers-Kouba, Algeria
- 110: Rostov, Russia
- 111: Piazzano Observatory, Florence, Italy
- 112: Pleiade Observatory, Verona, Italy
- 113: Volkssternwarte Drebach, Schönbrunn, Germany
- 114: Engelhardt Observatory, Zelenchukskaya Station, Russia (Kazan University Observatory (Обсерватория Казанского Университета); V. P. Engelhardt Astronomical Observatory (Астрономическая Обсерватория им. В. П. Энгельгардта))
- 115: Zelenchukskaya, Russia (Special Astrophysical Observatory (SAO); Специальная астрофизическая обсерватория (САО))
- 116: Giesing, Germany (München-Giesing)
- 117: Sendling, Munich, Germany
- 118: Astronomical and Geophysical Observatory, Modra, Slovakia (Astronomické observatórium Modra, Modra Observatory)
- 119: Abastuman, Georgia
- 120: Višnjan Observatory, Croatia (Zvjezdarnica Višnjan)
- 121: Kharkov University, Chuguevskaya Station, Ukraine
- 122: Pises Observatory, France (Observatoire des Pises)
- 123: Byurakan, Armenia
- 124: Castres, France (Observatoire de Castres)
- 125: Tbilisi, Georgia
- 126: Monte Viseggi, Italy (Osservatorio Astronomico di Monte Viseggi)
- 127: Bornheim, Germany
- 128: Saratov, Russia (Saratov State University)
- 129: Ordubad, Azerbaijan
- 130: Lumezzane, Italy (Osservatorio Astronomico "Serafino Zani")
- 131: Observatoire de l'Ardèche, France
- 132: Bédoin, France (Observatoire de Bédoin)
- 133: Les Tardieux, France
- 134: Groszschwabhausen
- 135: Kasan, Russia
- 136: Engelhardt Observatory, Kasan, Russia (Kazan University Observatory (Обсерватория Казанского Университета); V. P. Engelhardt Astronomical Observatory (Астрономическая Обсерватория им. В. П. Энгельгардта))
- 137: Givatayim Observatory, Israel
- 138: Village-Neuf, France
- 139: Antibes, France
- 140: Augerolles, France
- 141: Hottviller, France (Observatoire de Hottviller)
- 142: Sinsen, Germany
- 143: Gnosca, Switzerland (Osservatorio Astronomico di Gnosca)
- 144: Bray et Lu, France
- 145: 's-Gravenwezel, Belgium
- 146: Frignano, Italy
- 147: Osservatorio Astronomico di Suno, Italy
- 148: Guitalens, France (Observatoire de Guitalens)
- 149: Beine-Nauroy, France
- 150: Maisons Laffitte, France
- 151: Eschenberg Observatory, Winterthur, Switzerland (Sternwarte Eschenberg)
- 152: Moletai Astronomical Observatory, Lithuania (MAO; Molėtų astronomijos observatorija)
- 153: Stuttgart-Hoffeld, Germany
- 154: Cortina, Italy (Cortina d'Ampezzo, Associazione Astronomica Cortina: Osservatorio Astronomico del Col Drusciè "Helmut Ullrich")
- 155: Ole Romer Observatory, Aarhus
- 156: Catania Astrophysical Observatory, Sicily, Italy
- 157: Frasso Sabino (Osservatorio Astronomico Virginio Cesarini - Frasso Sabino, Italy)
- 158: Promiod (Osservatorio Dalai Lama di Promiod, Italy)
- 159: Monte Agliale (Osservatorio Astronomico di Monte Agliale, Italy)
- 160: Castelmartini, Italy
- 161: Cerrina Tololo Observatory, Italy
- 162: Potenza, Italy
- 163: Roeser Observatory, Luxembourg
- 164: St. Michel sur Meurthe, France
- 165: Piera Observatory, Barcelona, Spain (Observatori Astronomic de Piera)
- 166: Úpice, Czech Republic (Hvězdárna v Úpici)
- 167: Bülach Observatory, Switzerland
- 168: Kourovskaya, Russia
- 169: Airali Observatory, Italy
- 170: Observatorio de Begues, Spain
- 171: Flarestar Observatory, San Gwann, Malta
- 172: Onnens, Switzerland
- 173: St. Clotilde, Réunion, France (Observatoire Sainte-Clotilde)
- 174: Nyrölä Observatory, Jyväskylä, Finland (Nyrölän observatorio)
- 175: F.-X. Bagnoud Observatory, St-Luc, Switzerland (Bagnoud Observatory)
- 176: Observatorio Astronómico de Consell, Consell, Majorca, Spain (Consell Observatory)
- 177: Le Cres, France
- 178: Collonges, France
- 179: Monte Generoso, Switzerland
- 180: Mauguio, France
- 181: Observatoire des Makes, Saint-Louis, Réunion, France
- 182: St. Paul, Réunion, France
- 183: Starlab Observatory, Karachay-Cherkessia, Russia
- 184: Valmeca Observatory, Puimichel, France
- 185: Observatoire Astronomique Jurassien-Vicques, Switzerland
- 186: Kitab, Mt. Maydanak, Uzbekistan
- 187: Borowiec Astrogeodynamic Observatory, Borowiec, Poland
- 188: Majdanak, Uzbekistan
- 189: Geneva (before 1967), Switzerland
- 190: Gissar, Tajikistan
- 191: Dushanbe, Tajikistan
- 192: Tashkent, Uzbekistan
- 193: Sanglok, Tajikistan
- 194: Tivoli, Namibia
- 195: Untermenzing Observatory, Munich, Germany
- 196: Homburg-Erbach, Germany
- 197: Bastia, Italy
- 198: Wildberg (Observatorium Wildberg, Germany)
- 199: Buthiers (Observatoire de Buthiers, France)
Read more about this topic: List Of Observatory Codes