The number of visitors to Ireland dropped by over 18% in May, according to new figures from the Central Statistics Office.
Visits to this county fell by 18.4% in the fifth month of the year when compared to the same period in 2008.
The most affected market was those coming from Britain, with 306,400 people making the trip across the Irish Sea, representing a drop of nearly 23%.
Travellers from other areas of Europe amounted to 219,300, which is a fall of 20%.
The CSO figures also show that visits abroad by Irish residents declined by 10% to 610,000 in May.
For the first five months of the year, trips abroad were down 10.4% to 2,729,400. Similarly, the numbers coming to these shores fell by 9.6% to 2,667,500.
The Irish Tourist Industry Confederation said it expects the domestic tourism market to ‘hold its own’ despite the disappointing CSO figures for May.
In a statement released this evening, the ITIC said: 'The domestic market will be even more important than ever this year, and there is some evidence that the exceptionally attractive offers being made available by the industry are receiving a favourable consumer response.
'While the industry is not expecting a decline in the domestic market of anything near the overseas predictions, neither is it expecting growth in 2009,' it added.