| Bulgaria in Antarctica |
|---|
- Obelya Glacier, Sentinel Range
- Oberbauer Point, Anvers Island
- Obidim Peak, Trinity Peninsula
- Obitel Peninsula, Anvers Island
- Oborishte Ridge, Greenwich Island
- Obretenik Bastion, Danco Coast
- Obzor Hill, Trinity Peninsula
- Odesos Buttress, Nordenskjöld Coast
- Odometer Rock, Nelson Island
- Odrin Bay, Nordenskjöld Coast
- Oeagrus Beach Snow Island
- Oescus Island, Robert Island
- Ofelia Island, Joinville Island
- Ogled Peak, Trinity Peninsula
- Ognen Cove, Trinity Peninsula
- Ogosta Point, Livingston Island
- Ogoya Glacier, Trinity Peninsula
- Ograzhden Cove, Livingston Island
- Ogygia Island, Snow Island
- Ohoden Col, Trinity Peninsula
- Ojeda Beach, Livingston Island
- Okol Rocks, Aitcho Islands
- Okorsh Saddle, Oscar II Coast
- Olusha Cove, Trinity Island
- Omurtag Pass, Livingston Island
- Ongal Peak, Livingston Island
- Onogur Islands, Robert Island
- Opaka Rocks, Robert Island
- Opalchenie Peak, Vinson Massif
- Opitsvet Lake, Livingston Island
- Opizo Peak, Brabant Island
- Orbel Peak, Graham Coast
- Orcho Glacier, Clarence Island
- Oread Lake, Livingston Island
- Oreshak Peak, Sentinel Range
- Organa Peak, Smith Island
- Orizari Glacier, Sentinel Range
- Orpheus Gate, Livingston Island
- Orsini Rock, Livingston Island
- Orsoya Rocks, Robert Island
- Oryahovo Heights, Livingston Island
- Oselna Glacier, Alexander Island
- Osenovlag Island, Robert Island
- Oshane Glacier, Brabant Island
- Osikovo Ridge, Graham Coast
- Osmar Strait, South Shetland Islands
- Osogovo Bay, Livingston Island
- Ostrusha Nunatak, Sentinel Range
- Ovech Glacier, Smith Island