Founded on Dec 21, 1837, Delaware County is one of 99 counties in the state of Iowa. Historically, Delaware County was formed from Dubuque County and Wisconsin Territory. The city of Manchester is the county seat. With FIPS code of 55, Delaware County has a population of 17,510 and area of 578 square miles (1,497 km2).
List of all cities in Delaware County, IA alphabetically
| City/Town | Postal Code | Area Code |
| Colesburg, IA | 52035 | 563 |
| Delaware, IA | 52036 | 563 |
| 52057 | 563 | |
| Delhi, IA | 52223 | 563 |
| Dundee, IA | 52038 | 563 |
| Dutchtown, IA | 52057 | 563 |
| Earlville, IA | 52041 | 563 |
| Greeley, IA | 52050 | 563 |
| Hazel Green, IA | 52223 | 563 |
| Hopkinton, IA | 52237 | 563 |
| Manchester, IA | 52057 | 563 |
| Masonville, IA | 50654 | 563 |
| Oneida, IA | 52057 | 563 |
| Osterdock, IA | 52035 | 563 |
| Robinson, IA | 52330 | 563 |
| Ryan, IA | 52330 | 563 |
| Sand Spring, IA | 52237 | 563 |
| Thorpe, IA | 52057 | 563 |