Across the Line has been supporting new Irish music since 1986, first as The Bottom Line and then Across the Line . Bands such as Ash, Snow Patrol and Two Door Cinema club received their first airplay and sessions on ATL with former presenters such as Mike Edgar, Donna Legge, Colin Murray, Stuart Bailie, Paul McClean, Paul Hamill and Rory McConnell.

The Monday night radio show with current presenters Rigsy & Stuart Bailie is weighted towards rock and indie music with dance and electronica also represented.

The programme has regularly recorded live gigs and sessions and on occasion broadcasts live from venues across Northern Ireland with the occasional foray to the major Irish rock festivals.
A sister television series, ATL TV, ran from 2004 until 2009 featuring live performance, specially made videos for local bands and interviews from major recording artists.