Armagh jail was the subject of a private letter sent by the Prince of Wales to the Northern Ireland Office 11 years ago, it has emerged.
Prince Charles wrote to then Northern Ireland Secretary Paul Murphy offering his assistance in any plans for the conservation and reuse of the jail.
The Prince visited Armagh City on behalf of his mother Queen Elizabeth to confer city status in 1995.
In total 27 letters, sent to Labour government ministers about a decade ago, have been published after a lengthy legal battle.
Release of the letters follows a decade-long campaign by the Guardian.
The Prince of Wales wrote to Mr Murphy a week after staying at Hillsborough Castle, the Queen’s official residence in Northern Ireland.
The 27 letters, written to seven government departments between September 2004 and April 2005, were published on Wednesday with redactions.
A government veto on publication was declared unlawful by the Court of Appeal last year - a decision which was upheld by the Supreme Court in March.
Clarence House said the move would “only inhibit” the prince’s ability to express his concerns.