Founded in 1873, Clark County is one of 66 counties in the state of South Dakota. Historically, Clark County was formed from Hanson County. The city of Clark is the county seat. With FIPS code of 25, Clark County has a population of 3,855 and area of 958 square miles (2,481 km2).
List of all cities in Clark County, SD alphabetically
| City/Town | Postal Code | Area Code |
| Bloomfield, SD | 57322 | 605 |
| Bradley, SD | 57217 | 605 |
| Carpenter, SD | 57322 | 605 |
| Clark, SD | 57225 | 605 |
| Clark Colony, SD | 57258 | 605 |
| Crocker, SD | 57217 | 605 |
| Garden City, SD | 57236 | 605 |
| Naples, SD | 57271 | 605 |
| Raymond, SD | 57258 | 605 |
| Vienna, SD | 57271 | 605 |
| Willow Lake, SD | 57278 | 605 |