| Rockcastle | |
| Settlement Type: | Unincorporated community |
| Pushpin Map: | USA Kentucky#USA |
| Pushpin Label Position: | left |
| Pushpin Map Caption: | Location within the state of Kentucky |
| Subdivision Type: | Country |
| Subdivision Name: | United States |
| Subdivision Type1: | State |
| Subdivision Name1: | Kentucky |
| Subdivision Type2: | County |
| Subdivision Name2: | Trigg |
| Unit Pref: | Imperial |
| Population As Of: | 2000 |
| Population Density Km2: | auto |
| Timezone: | Central (CST) |
| Utc Offset: | -6 |
| Timezone Dst: | CST |
| Utc Offset Dst: | -5 |
| Elevation Ft: | 394 |
| Coordinates: | 36.8997°N -87.9872°W |
| Postal Code Type: | ZIP codes |
| Blank Name: | FIPS code |
| Blank1 Name: | GNIS feature ID |
| Blank1 Info: | 508957 |
Rockcastle, formerly Rock Castle, is an unincorporated community in Trigg County, Kentucky, United States.
A post office was in operation at Rockcastle from 1839 until 1915.[1] The community derives its name from a nearby rock formation called Castle Rock.[2] for strategic reasons rockcastle was burned during the war. Old Rockcastle now lies under lake barkley