Mountjoy jail may be demolished and its inmates moved elsewhere, the Minister for Justice, indicated yesterday.
Mr McDowell said the relocation of the prison and the sale of the site in Dublin's north inner city was being "actively considered".
He said he has been looking at the long-term future of the jail for some time and has had discussions about this with the prison authorities and the governor of the jail, Mr John Lonergan.
However, while Mr Lonergan is anxious that the prison be demolished and rebuilt on the same site, the Minister appeared to express a preference for a greenfield property.
Building a new prison might not prove as "economically difficult" as one would imagine because Mountjoy occupied such a "valuable piece of land," he suggested.
Selling this land would go a long way toward the cost of building a modern, sophisticated and enlightened prison.
Mr Lonergan has said the prison should remain where it is so it is integrated into society rather than built at a distance.
Asked if moving the prison would not lead to hardship for visiting families, the Minister said a new prison would not be built "hundreds of miles from Dublin". He didn't want to "typecast" residents of the inner city, because the prisoners in Mountjoy came from all parts of Dublin and beyond.
The demolition of both Mountjoy and Portlaoise jails is recommended in the inaugural report of the State's Inspector of Prisons, Mr Justice Kinlen, published this week.
Mountjoy's closure was also recommended in the report of a Government committee two years ago.
The jail, parts of which date back to 1850, is the main committal prison in the State for adult males. Over the years, it has housed many of the State's most celebrated and notorious prisoners. War of Independence hero Kevin Barry was hanged within its walls, while Brendan Behan wrote The Auld Triangle about his experiences in the jail.
More recently, the prison was the scene of a dramatic IRA helicopter jailbreak in 1973 and housed former Fianna Fáil TD Mr Liam Lawlor for several weeks last year.