Boulder, Illinois | |
|---|---|
  Boulder, Illinois  Boulder, Illinois | |
| Coordinates: 38°41′48″N 89°13′32″W / 38.69667°N 89.22556°W | |
| Country | United States |
| State | Illinois |
| County | Clinton |
| Elevation | 466 ft (142 m) |
| Time zone | UTC-6 (Central (CST)) |
| • Summer (DST) | UTC-5 (CDT) |
| Area code | 618 |
| GNIS feature ID | 404717[1] |
Boulder is an unincorporated community in Clinton County, Illinois, United States. Boulder is located on the eastern shore of Carlyle Lake; a railroad line crosses the lake from Boulder to Keyesport.
