The monastic ruins at Clonmacnoise, Co Offaly, have been recommended for designation as a UNESCO World Heritage site by the Minister for the Environment, Mr Cullen.
Ireland's other world heritage sites include Brú na Bóinne, Co Meath - which includes Newgrange and Knowth - and Skellig Michael, off the coast of Co Kerry. In 2002, Clonmacnoise attracted 159,000 visitors.
Mr Cullen today launched a draft Management Plan for the site which provided comprehensive information on various aspects of Clonmacnoise from its management history, its wide and varied resources through to visitor management policies.
The draft plan proposes a number of key actions under the headings of protection, conservation, presentation and research.
The Minister said that as an area of both natural and cultural significance, Clonmacnoise was worthy of joining Brú na Bóinne and Skellig Michael as a World Heritage Site.
He added: "The Government's focus in managing the archaeological area at Clonmacnoise is to ensure the protection of the site's cultural and natural heritage and to conserve and present the area of the site in State care for the benefit of Co Offaly, the nation and for future generations.
"There are many, both locally in Offaly and nationwide with an interest in our national heritage. I would encourage people to make their valued input into the future management policy at Clonmacnoise".
The Minister said that, while work on the application would commence shortly, it would not be finalised until the consultation process on the draft plan had been completed.