The Auld Triangle is a song written by Dominic Behan and is featured in his brother Brendan's play The Quare Fellow. It is used to introduce the play, a story about the occurrences in a prison (in real life Mountjoy Prison where Behan had once been lodged) the day a convict is set to be executed. The triangle in the title refers to the large metal triangle which was beaten daily in Mountjoy Prison to waken the inmates ("The Auld Triangle goes Jingle Jangle"). The triangle still hangs in the prison at the centre where the wings meet on a metal gate. It is no longer used, though the hammer to beat it is mounted beside it. The song has also become known as "The Banks of the Royal Canal."

The song has taken on a sort of life of its own and has gone beyond its status of a song in a play, developing into a modern Irish anthem. Musical groups as diverse as The Dubliners, The Pogues, The Doug Anthony Allstars and, most recently, U2, Dropkick Murphys, the High Kings, and Poor Angus have covered the song. An unusual live version, recorded at Glasgow Royal Concert Hall, appears on the live debut album The Dawning of the Day by Dublin based pipe band St. Laurence O' Toole. As with many Irish ballads, the lyrics have been changed with each passing cover. For example, the Murphys' cover condenses the structure into a three-lyric section song with a chorus based on the last two lines of each stanza in the original. The Swell Season have also included the song in their live performances.

Bob Dylan and The Band also recorded a rendition of the song during their famed Basement Tapes sessions in 1967. This recording is widely available via bootleg. It has also been recorded by Bert Jansch and appears on his 2006 album The Black Swan. The song has also been recorded by Jeff Tweedy on his tour DVD Sunken Treasure: Live in the Pacific Northwest, and sung live by the Oysterband: it appears on their now-deleted 'Alive and Acoustic' recording.

Eric Burdon also recorded a version of it, retitled "The Royal Canal".

The Lyrics:

A hungry feeling, came o'er me stealing
All the mice were squealing in my prison cell
And the old triangle, went jingle jangle
All along the banks of the Royal Canal.
To begin the morning, the screw bawling
Get up ya bowsie and clean up your cell
And the old triangle went jingle jangle
All along the banks of the Royal Canal.
The lags were sleeping, Humpy Gussy was peeping
As I lay there weeping for my gal Sal
And the old triangle went jingle jangle
All along the banks of the Royal Canal.
On a fine spring evening, the lag lay dreaming
The seagulls wheeling high above the wall
And the old triangle went jingle jangle
All along the banks of the Royal Canal.
The day was dying and the wind was sighing
As I lay there crying in my prison cell
And the old triangle, went jingle jangle
All along the banks of the Royal Canal.
Up in the female prison there are seventy women
And among them I wish I did dwell
Then the old triangle could go jingle jangle
All along the banks of the Royal Canal.
All along the banks of the Royal Canal.