| Name | What | Region | Country | Lat | Long | Elev ft. | Pop est |
|---|---|---|---|---|---|---|---|
| Osa | city | Italy | 42.73 | 12.23 | 587 | 6118 | |
| Osacca | city | Italy | 44.55 | 9.75 | 2939 | 2798 | |
| Osarella | city | Italy | 42.73 | 12.17 | 908 | 7307 | |
| Oschiri | city | Regione Autonoma della Sardegna | Italy | 40.72 | 9.10 | 810 | 1760 |
| Oseacco | city | Regione Autonoma Friuli-Venezia Giulia | Italy | 46.36 | 13.31 | 1486 | 911 |
| Osera | city | Italy | 44.80 | 9.50 | 987 | 2096 | |
| Osidda | city | Regione Autonoma della Sardegna | Italy | 40.52 | 9.22 | 1975 | 2029 |
| Osiglia | city | Italy | 44.28 | 8.20 | 2575 | 2612 | |
| Osigo | city | Regione del Veneto | Italy | 46.01 | 12.34 | 787 | 21045 |
| Osilo | city | Regione Autonoma della Sardegna | Italy | 40.75 | 8.67 | 2066 | 7741 |
| Osimo | city | Italy | 43.48 | 13.48 | 288 | 29610 | |
| Osini | city | Regione Autonoma della Sardegna | Italy | 39.83 | 9.49 | 1640 | 3153 |
| Oslavia | city | Regione Autonoma Friuli-Venezia Giulia | Italy | 45.97 | 13.61 | 275 | 51305 |
| Osmate | city | Italy | 45.78 | 8.65 | 1181 | 34058 | |
| Osmate Lentate | city | Italy | 45.78 | 8.65 | 1181 | 34058 | |
| Osnago | city | Italy | 45.67 | 9.38 | 744 | 89641 | |
| Osoli | city | Italy | 42.85 | 13.43 | 1607 | 4398 | |
| Osoppo | city | Regione Autonoma Friuli-Venezia Giulia | Italy | 46.26 | 13.08 | 554 | 13390 |
| Ospanesco | city | Italy | 42.22 | 13.10 | 2864 | 2237 | |
| Ospedaletti | city | Italy | 43.80 | 7.72 | 0 | 35697 | |
| Ospedaletto | city | Regione Autonoma Friuli-Venezia Giulia | Italy | 46.30 | 13.12 | 820 | 15337 |
| Ospedaletto | city | Italy | 46.05 | 11.55 | 1456 | 4930 | |
| Ospedaletto | city | Regione del Veneto | Italy | 45.66 | 12.08 | 68 | 28013 |
| Ospedaletto | city | Italy | 43.98 | 12.57 | 173 | 33977 | |
| Ospedaletto | city | Italy | 43.70 | 10.42 | 6 | 45124 | |
| Ospedaletto | city | Italy | 42.77 | 13.05 | 3582 | 1603 | |
| Ospedaletto | city | Regione Emilia-Romagna | Italy | 44.24 | 12.08 | 32 | 46051 |
| Ospedaletto Euganeo | city | Italy | 45.22 | 11.60 | 26 | 23581 | |
| Ospedaletto d'Alpinolo | city | Italy | 40.93 | 14.75 | 1640 | 70222 | |
| Ospedaletto d’Alpinolo | city | Italy | 40.93 | 14.75 | 1640 | 70222 | |
| Ospedalicchio | city | Italy | 43.08 | 12.50 | 629 | 36430 | |
| Ospitale | city | Regione del Veneto | Italy | 46.33 | 12.32 | 1545 | 2305 |
| Ospitale | city | Italy | 44.90 | 11.43 | 32 | 9421 | |
| Ospitale | city | Italy | 44.17 | 10.78 | 3211 | 3249 | |
| Ospitale Bellunese | city | Regione del Veneto | Italy | 46.33 | 12.32 | 1545 | 2305 |
| Ospitale Monacale | city | Italy | 44.67 | 11.70 | 16 | 7944 | |
| Ospitale di Brenta | city | Italy | 45.62 | 11.70 | 101 | 31303 | |
| Ospitale di Cadore | city | Regione del Veneto | Italy | 46.33 | 12.32 | 1545 | 2305 |
| Ospitaletto | city | Italy | 45.55 | 10.07 | 439 | 55198 | |
| Ospitaletto | city | Italy | 45.53 | 9.15 | 426 | 488167 | |
| Ospitaletto | city | Italy | 45.13 | 10.60 | 52 | 8330 | |
| Ospitaletto | city | Italy | 44.30 | 10.32 | 4232 | 1569 | |
| Ospitaletto di Cormono | city | Italy | 45.53 | 9.15 | 426 | 488167 | |
| Ospizio San Carlo | city | Italy | 44.45 | 11.42 | 223 | 82470 | |
| Ossago | city | Italy | 45.23 | 9.53 | 196 | 16813 | |
| Ossaia | city | Italy | 43.23 | 12.00 | 1190 | 18512 | |
| Ossenigo | city | Italy | 45.67 | 10.90 | 1286 | 4851 | |
| Ossi | city | Regione Autonoma della Sardegna | Italy | 40.68 | 8.59 | 1335 | 16445 |
| Ossiach | city | Regione Autonoma Friuli-Venezia Giulia | Italy | 46.18 | 13.50 | 2706 | 3204 |
| Ossona | city | Italy | 45.50 | 8.90 | 488 | 83362 | |
| Ost | city | Italy | 44.78 | 10.70 | 65 | 25533 | |
| Ostellato | city | Italy | 44.75 | 11.93 | 16 | 6801 | |
| Osteno | city | Italy | 46.00 | 9.08 | 2660 | 8297 | |
| Ostera Braccagni | city | Italy | 42.88 | 11.08 | 452 | 5484 | |
| Osteria Alpina | city | Italy | 46.13 | 11.47 | 3802 | 3355 | |
| Osteria Boscara | city | Italy | 45.37 | 12.08 | 16 | 38175 | |
| Osteria Boscaro | city | Italy | 45.37 | 12.08 | 16 | 38175 | |
| Osteria Carlettani | city | Italy | 46.15 | 11.52 | 5124 | 3525 | |
| Osteria Carlettini | city | Italy | 46.15 | 11.52 | 5124 | 3525 | |
| Osteria Marcesina | city | Italy | 45.97 | 11.60 | 4484 | 3798 | |
| Osteria del Forcelletto | city | Italy | 45.88 | 11.75 | 3907 | 7154 | |
| Osteria dell' Osa | city | Italy | 41.88 | 12.70 | 164 | 130373 | |
| Osteria dell’ Osa | city | Italy | 41.88 | 12.70 | 164 | 130373 | |
| Osteria di Marcesina | city | Italy | 45.97 | 11.60 | 4484 | 3798 | |
| Osteria di Marcesna | city | Italy | 45.97 | 11.60 | 4484 | 3798 | |
| Osteria di Novoli | city | Italy | 43.95 | 11.32 | 810 | 11731 | |
| Osteria di Potassa | city | Italy | 42.95 | 10.93 | 314 | 6657 | |
| Osteriaccia | city | Regione Emilia-Romagna | Italy | 44.18 | 12.30 | 32 | 32491 |
| Osteriola | city | Italy | 44.58 | 11.42 | 45 | 34354 | |
| Osteto | city | Italy | 44.07 | 11.42 | 2595 | 2787 | |
| Ostia | city | Italy | 41.75 | 12.30 | 13 | 149873 | |
| Ostia Antica | city | Italy | 41.75 | 12.30 | 13 | 149873 | |
| Ostia Lido | city | Italy | 41.73 | 12.27 | 0 | 85581 | |
| Ostia Parmense | city | Italy | 44.52 | 9.85 | 1604 | 3289 | |
| Ostiano | city | Italy | 45.22 | 10.25 | 101 | 9662 | |
| Ostiglia | city | Italy | 45.07 | 11.13 | 19 | 12266 | |
| Ostigliano | city | Italy | 40.32 | 15.15 | 1624 | 4111 | |
| Ostra | city | Italy | 43.60 | 13.05 | 587 | 10985 | |
| Ostra | city | Italy | 43.62 | 13.15 | 347 | 15900 | |
| Ostra Vetere | city | Italy | 43.60 | 13.05 | 587 | 10985 | |
| Ostuni | city | Italy | 40.73 | 17.58 | 633 | 19471 |