Founded in 1800, Armstrong County is one of 67 counties in the state of Pennsylvania. Historically, Armstrong County was formed from parts of Allegheny, Lycoming, and Westmoreland Counties. The city of Kittanning is the county seat. With FIPS code of 5, Armstrong County has a population of 65,093 and area of 664 square miles (1,720 km2).
List of all cities in Armstrong County, PA alphabetically
| City/Town | Postal Code | Area Code |
| Adrian, PA | 16210 | 724/878 |
| Cadogan, PA | 16212 | 724/878 |
| Cowansville, PA | 16218 | 724/878 |
| Craigsville, PA | 16262 | 724/878 |
| Dayton, PA | 16222 | 814 |
| Distant, PA | 16223 | 814 |
| Elderton, PA | 15736 | 724/878 |
| Ford City, PA | 16226 | 724/878 |
| Ford Cliff, PA | 16228 | 724/878 |
| Freeport, PA | 16229 | 724/878 |
| Kittanning, PA | 16201 | 724/878 |
| Leechburg, PA | 15656 | 724/878 |
| Manorville, PA | 16238 | 724/878 |
| McGrann, PA | 16236 | 724/878 |
| North Apollo, PA | 15673 | 724/878 |
| North Leechburg, PA | 15656 | 724/878 |
| Nu Mine, PA | 16244 | 724/878 |
| Oak Ridge, PA | 16245 | 814 |
| Parker, PA | 16049 | 724/878 |
| Rural Valley, PA | 16249 | 724/878 |
| Sagamore, PA | 16250 | 724/878 |
| Schenley, PA | 15682 | 724/878 |
| Seminole, PA | 16253 | 814 |
| Spring Church, PA | 15686 | 724/878 |
| Templeton, PA | 16259 | 724/878 |
| West Leechburg, PA | 15656 | 724/878 |
| Widnoon, PA | 16261 | 724/878 |
| Worthington, PA | 16262 | 724/878 |
| Yatesboro, PA | 16263 | 724/878 |