Red Gap
Red Gap is a hill around 400 feet above sea level, 16 kilometres southwest of Dublin city centre in the Dublin Mountains at Saggart. It is also known as Saggart Hill or Slieve Thoul. Today, Red Gap is home to farmland and telecommunication masts. The hill has FM radio transmitters for Newstalk, Kfm, LMFM, i105-107 and East Coast FM.
The hill is also home to low-power fill in transmitters of Nova 100 and 4FM, designed to cover the Dublin commuter belt
The old time song 'Campbell's farewell to Red Gap' is believed to be referring to this hill.
Radio transmissions
| Frequency | Station | Power | Notes |
| 94.6 | Classic Hits 4FM | 0.1 | Covers commuter belt area of County Kildare and County Meath. |
| 95.5 | LMFM | 2 | Covers south County Meath. Notable for being well outside the stations coverage area of Counties Meath and Louth and provides significant coverage into North County Dublin |
| 97.6 | Kfm | 1 | Directional signal into County Kildare. |
| 99.9 | East Coast FM | 2 | Directional signal into County Wicklow. Moved from 94.9 in 2005. |
| 100.5 | Radio Nova 100 | 0.1 | Covers commuter belt area of County Kildare and County Meath. |
| 104.7 | iRadio | 4.95 | Provides coverage of County Kildare and County Meath. |
| 107.6 | Newstalk | 1 |