| Name | Country | Feature class | Latitude | Longitude | |
|---|---|---|---|---|---|
1501  | Oratta  Oratta | Nigeria, Imo State Owerri North | populated place | N 5° 29′ 40'' | E 7° 4′ 23'' |
| 1502 | Opi Opi | Nigeria, Enugu State Nsukka | populated place population 11,237 | N 6° 46′ 56'' | E 7° 25′ 59'' |
| 1503 | Onne Awne,Onne | Nigeria, Rivers State Eleme | populated place | N 4° 43′ 28'' | E 7° 9′ 9'' |
| 1504 | Omupo Omupo | Nigeria, Kwara State Ifelodun | populated place | N 8° 16′ 29'' | E 4° 47′ 44'' |
1505  | Oloyan Forest Reserve Ilorin Native Area Number 4,Oloyan Forest Reserve | Nigeria, Oyo State | forest reserve | N 8° 5′ 8'' | E 4° 30′ 23'' |
| 1506 | Olomu Olomu | Nigeria, Osun State Ife South | populated place | N 7° 11′ 58'' | E 4° 27′ 49'' |
| 1507 | Oloibiri Olobiri,Oloibiri,Oloimpiri,Ολοϊμπίρι | Nigeria, Bayelsa State Ogbia | populated place | N 4° 40′ 18'' | E 6° 18′ 48'' |
1508  | Ologe Lagoon Ologe Lagoon,Oluge Lagoon | Nigeria, Lagos | lake | N 6° 28′ 14'' | E 3° 5′ 0'' |
| 1509 | Okpogho Okpogbo,Okpogho,Okpogkho,Окпогхо | Nigeria, Enugu State Ezeagu | populated place | N 6° 26′ 0'' | E 7° 16′ 19'' |
| 1510 | Okpe-Olomu Okpe,Okpe-Olomu | Nigeria, Delta Ughelli South | populated place | N 5° 25′ 44'' | E 5° 56′ 48'' |
| 1511 | Oke Onigbin Oke Onigbin | Nigeria, Kwara State Isin | populated place | N 8° 13′ 19'' | E 4° 59′ 57'' |
| 1512 | Okenyi Oken,Okenyi | Nigeria, Kogi State Ankpa | populated place | N 7° 18′ 14'' | E 7° 45′ 52'' |
| 1513 | Okemu Okemu,Okemue,Okemuen,Okemwa | Nigeria, Edo State Uhunmwonde | populated place | N 6° 39′ 52'' | E 6° 0′ 54'' |
| 1514 | Okanle Okanle | Nigeria, Kwara State Ifelodun | populated place | N 8° 19′ 0'' | E 4° 42′ 0'' |
| 1515 | Ojo Awjaw,Ojo,Ojoh | Nigeria, Lagos Ojo | populated place | N 6° 28′ 6'' | E 3° 10′ 59'' |
| 1516 | Ohunbe Forest Reserve Ohumbe Forest Reserve,Ohunbe Forest Reserve | Nigeria, Ogun State | forest reserve | N 6° 55′ 45'' | E 2° 48′ 17'' |
| 1517 | Ohordwa Ohordua,Ohordwa,Uokhuelen-Ohordua | Nigeria, Edo State Esan South-East | populated place | N 6° 31′ 39'' | E 6° 24′ 39'' |
| 1518 | Ogurugu Ogrugru,Ogurugu | Nigeria, Kogi State | populated place population 9,135 | N 6° 47′ 10'' | E 6° 57′ 0'' |
| 1519 | Ogun Forest Reserve Ogun Forest Reserve,Ogun River | Nigeria, Lagos | forest reserve | N 6° 37′ 32'' | E 3° 26′ 19'' |
| 1520 | Ogbunike Ogbirnike,Ogbunike | Nigeria, Anambra Idemili North | populated place | N 6° 9′ 53'' | E 6° 53′ 25'' |
| 1521 | Ogbesse Forest Reserve Ogbesse Forest Reserve,Ogbesse River | Nigeria, Ekiti State | forest reserve | N 7° 32′ 22'' | E 5° 21′ 43'' |
| 1522 | Ofagbe Ofagbe | Nigeria, Delta Isoko North | populated place | N 5° 32′ 57'' | E 6° 20′ 33'' |
| 1523 | Odo-Ogun Forest Reserve Odo Ogun Forest Reserve,Odo-Ogun Forest Reserve,Odo-OgunForestReserve,OdoOgunForestReserve | Nigeria, Oyo State | forest reserve | N 7° 54′ 15'' | E 3° 43′ 37'' |
| 1524 | Odioma Odiama,Odioma | Nigeria, Bayelsa State Brass | populated place | N 4° 19′ 44'' | E 6° 25′ 55'' |
| 1525 | Odige Odige,Odigi,Odigie | Nigeria, Edo State Etsako West | populated place | N 6° 52′ 4'' | E 6° 17′ 1'' |
| 1526 | Ochobo Ochobo,Ochobu | Nigeria, Benue State Ohimini | populated place population 8,567 | N 7° 10′ 49'' | E 7° 58′ 56'' |
| 1527 | Ochicha Ngugo Ochicha Ngugo | Nigeria, Imo State Ikeduru | populated place | N 5° 34′ 46'' | E 7° 8′ 44'' |
| 1528 | Obot-Akara Obot-Akara | Nigeria, Akwa Ibom State Obot Akara | populated place | N 5° 16′ 18'' | E 7° 39′ 29'' |
| 1529 | Obosi Obosi | Nigeria, Anambra Idemili North | populated place | N 6° 5′ 55'' | E 6° 48′ 29'' |
| 1530 | Obomkpa Obomkpa | Nigeria, Delta Aniocha North | populated place | N 6° 24′ 54'' | E 6° 29′ 17'' |
| 1531 | Obiribe Obiribe,Obiribiri | Nigeria, Cross River State | locality | N 5° 22′ 32'' | E 8° 26′ 38'' |
| 1532 | Obior Obbio,Obior,Obor | Nigeria, Delta Aniocha North | populated place | N 6° 16′ 8'' | E 6° 22′ 40'' |
| 1533 | Obinze Obinze | Nigeria, Imo State Owerri West | populated place | N 5° 24′ 31'' | E 6° 57′ 34'' |
| 1534 | Obilokwu Mbieri Obilokwa Mbieri,Obilokwu Mbieri | Nigeria, Imo State Ikeduru | populated place | N 5° 32′ 0'' | E 7° 6′ 0'' |
| 1535 | Amafor Amafor,Obigwe,Obigwo | Nigeria, Imo State Owerri West | populated place | N 5° 27′ 45'' | E 6° 53′ 7'' |
| 1536 | Obi Forest Reserve Lafia Native Area Number 2,Obi Forest Reserve | Nigeria, Nasarawa State | forest reserve | N 8° 21′ 13'' | E 8° 43′ 29'' |
1537  | Oban Hills Oban Hills | Nigeria, | hills | N 5° 30′ 0'' | E 8° 35′ 0'' |
| 1538 | Oba Hill Forest Reserve Oba Hill Forest Reserve,Oba Hills | Nigeria, Osun State | forest reserve | N 7° 46′ 10'' | E 4° 5′ 51'' |
| 1539 | Obadan Obadan | Nigeria, Edo State Uhunmwonde | populated place | N 6° 28′ 32'' | E 5° 54′ 17'' |
| 1540 | Oba Oba | Nigeria, Anambra Idemili South | populated place | N 6° 4′ 10'' | E 6° 50′ 21'' |
| 1541 | Nyunkun Lake Lake Nyunkun,Nyunkun Lake | Nigeria, Taraba State | lake | N 8° 19′ 36'' | E 10° 34′ 37'' |
| 1542 | Nsugbe Nsugbe | Nigeria, Anambra Anambra East | populated place | N 6° 15′ 49'' | E 6° 49′ 8'' |
| 1543 | Nok Nok | Nigeria, Kaduna State Jaba > Nok culture | populated place | N 9° 29′ 24'' | E 8° 1′ 16'' |
| 1544 | Nobi Nnabi,Nnobi,Nobi | Nigeria, Anambra Idemili South | populated place | N 6° 2′ 48'' | E 6° 56′ 28'' |
| 1545 | Nkwesi Nkwesi | Nigeria, Imo State Mbatoli | populated place | N 5° 35′ 54'' | E 7° 1′ 31'' |
| 1546 | Nkwerre Nkwerre | Nigeria, Imo State Nkwerre | seat of a second-order administrative division population 62,973 | N 5° 45′ 33'' | E 7° 6′ 13'' |
| 1547 | Nkalu Nkalu | Nigeria, Akwa Ibom State Ini | populated place | N 5° 24′ 9'' | E 7° 39′ 20'' |
| 1548 | Njiddawo Lake Lake Njiddawo,Njiddawo Lake | Nigeria, Taraba State | lake | N 8° 22′ 24'' | E 10° 31′ 19'' |
| 1549 | Nibo-Nise Nibo,Nibo-Nise | Nigeria, Anambra Awka South | populated place | N 6° 10′ 19'' | E 7° 4′ 2'' |
| 1550 | Nguroje Guroji,Nguroje,Old Mbungnu | Nigeria, Taraba State Sardauna | populated place | N 6° 57′ 36'' | E 11° 6′ 58'' |
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