| Castlehill | |
| Native Name: | Irish: Caorthannán |
| Native Name Lang: | ga |
| Settlement Type: | Village |
| Pushpin Map: | Ireland |
| Pushpin Label Position: | right |
| Pushpin Map Caption: | Location in Ireland |
| Subdivision Type: | Country |
| Subdivision Name: | Ireland |
| Subdivision Type1: | Province |
| Subdivision Name1: | Connacht |
| Subdivision Type3: | County |
| Subdivision Name3: | County Mayo |
| Unit Pref: | Metric |
| Population As Of: | 2002 |
| Population Density Km2: | auto |
| Utc Offset1: | +0 |
| Timezone1 Dst: | IST (WEST) |
| Utc Offset1 Dst: | -1 |
| Coordinates: | 54.0517°N -9.3392°W |
| Elevation M: | 24 |
| Blank Name: | Irish Grid Reference |
Castlehill is a townland and village near the west coast of Lough Conn in County Mayo, Ireland. Historically it was called Keerhannaun or Keerhanaun, which are anglicisations of its Irish name.[1]