| Name | What | Region | Country | Lat | Long | Elev ft. | Pop est |
|---|---|---|---|---|---|---|---|
| Onka-yaing | city | Shan State | Burma | 21.47 | 96.64 | 1669 | 2086 |
| Onkala | city | Plateaux | Congo | -2.32 | 14.54 | 2509 | 596 |
| Onkalo | city | Lappi | Finland | 65.62 | 25.07 | 39 | 172 |
| Onkamaa | city | Kymenlaakso | Finland | 60.65 | 27.40 | 147 | 222 |
| Onkamo | city | Norra Karelen | Finland | 62.33 | 30.03 | 324 | 446 |
| Onkamo | city | Lappi | Finland | 66.75 | 29.10 | 980 | 10 |
| Onkamo | city | Norra Karelen | Finland | 62.30 | 30.17 | 380 | 447 |
| Onkamojärvi | city | Lappi | Finland | 66.75 | 29.10 | 980 | 10 |
| Onkamon Kannas | city | Norra Karelen | Finland | 62.33 | 30.03 | 324 | 446 |
| Onkamus | city | Kareliya | Russia | 62.14 | 33.03 | 413 | 107 |
| Onkanas | city | Man, Isle of | 54.18 | -4.45 | 150 | 22934 | |
| Onkara | city | Haut-Ogooue | Gabon | -1.49 | 14.06 | 2001 | 149 |
| Onkarpur | city | Madhya Pradesh | India | 24.22 | 77.12 | 1669 | 20841 |
| Onkasa | city | Lekoumou | Congo | -2.81 | 13.71 | 1942 | 423 |
| Onkasa II | city | Lekoumou | Congo | -2.80 | 13.68 | 1991 | 421 |
| Onkassa | city | Lekoumou | Congo | -2.81 | 13.71 | 1942 | 423 |
| Onkassa II | city | Lekoumou | Congo | -2.80 | 13.68 | 1991 | 421 |
| Onkemaeki | city | Birkaland | Finland | 61.25 | 23.58 | 321 | 581 |
| Onkemäki | city | Birkaland | Finland | 61.25 | 23.58 | 321 | 581 |
| Onkerzeele | city | Vlaanderen | Belgium | 50.78 | 3.91 | 91 | 32187 |
| Onkerzele | city | Vlaanderen | Belgium | 50.78 | 3.91 | 91 | 32187 |
| Onkey | city | Plateaux | Congo | -2.16 | 15.87 | 1669 | 298 |
| Onkfeld | city | Nordrhein-Westfalen | Germany | 51.22 | 7.35 | 1204 | 27037 |
| Onkhadri | city | Himachal Pradesh | India | 30.61 | 77.39 | 2509 | 13490 |
| Onkhakov | city | Khakasiya | Russia | 53.02 | 90.33 | 1249 | 351 |
| Onkhoyek | city | Zabaykal'skiy Kray | Russia | 50.35 | 113.03 | 2631 | 149 |
| Onkijoki | city | Varsinais-Suomi | Finland | 60.90 | 23.08 | 324 | 3903 |
| Onkilahti | city | Pohjois-Savo | Finland | 63.37 | 27.20 | 242 | 584 |
| Onkilampi | city | Kareliya | Russia | 61.73 | 32.15 | 321 | 0 |
| Onkimaa | city | Nyland | Finland | 60.57 | 25.35 | 206 | 2027 |
| Onkimaa | city | Nyland | Finland | 60.55 | 25.58 | 121 | 1322 |
| Onkimaeki | city | Norra Karelen | Finland | 62.58 | 30.70 | 830 | 149 |
| Onkimaki | city | Norra Karelen | Finland | 62.58 | 30.70 | 830 | 149 |
| Onkiniemi | city | Paijat-Hame | Finland | 61.42 | 26.03 | 830 | 421 |
| Onkis | city | Varsinais-Suomi | Finland | 60.25 | 21.62 | 6 | 146 |
| Onkiélé | city | Plateaux | Congo | -2.67 | 15.30 | 2004 | 149 |
| Onkjer | city | Upper Nile | South Sudan | 10.35 | 32.32 | 1249 | 0 |
| Onkkori | city | Kainuu | Finland | 64.25 | 26.95 | 830 | 122 |
| Onklou | city | Benin | 9.50 | 1.98 | 1059 | 1937 | |
| Onko | city | Katanga | Congo (Dem. Republic of The)-(Zaire) | -4.12 | 19.98 | 1669 | 661 |
| Onko | city | Togo | 8.13 | 1.55 | 830 | 4619 | |
| Onko II | city | Katanga | Congo (Dem. Republic of The)-(Zaire) | -4.17 | 19.93 | 1145 | 25551 |
| Onkohsi | city | Oshikoto | Namibia | -18.92 | 17.23 | 3717 | 149 |
| Onkojek | city | Zabaykal'skiy Kray | Russia | 50.35 | 113.03 | 2631 | 149 |
| Onkolde | city | Tana River | Kenya | -2.32 | 40.20 | 101 | 6245 |
| Onkon | city | Ayeyawady | Burma | 17.35 | 95.36 | 42 | 25477 |
| Onkonoso | city | Plateaux | Congo | -1.51 | 15.91 | 1223 | 357 |
| Onkonosso | city | Plateaux | Congo | -1.51 | 15.91 | 1223 | 357 |
| Onkotsu | city | Hokkaido | Japan | 44.42 | 146.33 | 65 | 326 |
| Onkoua | city | Haut-Ogooue | Gabon | -1.79 | 13.83 | 1669 | 368 |
| Onkouma | city | Lekoumou | Congo | -2.92 | 13.90 | 2001 | 447 |
| Onkouta | city | Hokkaido | Japan | 42.12 | 139.52 | 0 | 986 |
| Onkouéwata | city | Benin | 10.54 | 1.13 | 830 | 272 | |
| Onkoyek | city | Zabaykal'skiy Kray | Russia | 50.35 | 113.03 | 2631 | 149 |
| Onkraj Meže | city | Mezica | Slovenia | 46.52 | 14.85 | 1699 | 7531 |
| Onkrengkhi | city | Kayin State | Burma | 16.15 | 98.78 | 1669 | 701 |
| Onks | city | Tennessee | United States | 36.30 | -82.44 | 1797 | |
| Onkuchakh | city | Sakha (Yakutiya) | Russia | 66.23 | 114.70 | 928 | 0 |
| Onkugakh | city | Sakha (Yakutiya) | Russia | 66.23 | 114.70 | 928 | 0 |
| Onkumbwiimbwi | city | Oshana | Namibia | -18.03 | 16.00 | 3536 | 1287 |
| Onkwankus | city | Congo (Dem. Republic of The)-(Zaire) | -1.99 | 19.54 | 1669 | 1341 | |
| Onkwankusu | city | Congo (Dem. Republic of The)-(Zaire) | -1.99 | 19.54 | 1669 | 1341 | |
| Onkwinkwiti | city | Oshikoto | Namibia | -17.90 | 17.15 | 3713 | 354 |
| Onkārpura | city | Rajasthan | India | 25.41 | 74.27 | 1669 | 17093 |
| Onkūr | city | Andhra Pradesh | India | 18.08 | 82.41 | 3349 | 12102 |