Almost 1.8 million people visited Ireland between April and June, a 15.6 per cent increase on the same period last year.
Quarterly figures from the Central Statistics Office show a significant increase in the number arriving from the UK, North America and Europe.
The surge came during a period when Queen Elizabeth II and US president Barack Obama visted Ireland and the Aviva Stadium hosted the UEFA Europa League final between Portguese sides Porto and Braga.
However, the corresponding period in 2010 was particularly difficult for the tourist industry with hundreds of European flights cancelled in April and May as a result of the volcanic ash cloud.
When compared to the same period in 2009, there was a decrease of about 120,000 in the number of visitors to Ireland with the largest drop off in the key UK market where visitor numbers fell by about 11 per cent from 858,000 to 761,000.
The most recent figures show growth in the numbers travelling here from North America. Visitor numbers rose from 264,000 last year to 308,800, which represented a 1 per cent rise on the 2009 figure.
The numbers arriving from Europe, the market hardest hit by the ash cloud last year, recovered from 500,500 to 620,700. However, the number of Europeans travelling to Ireland was more than 37,000 lower than in the same period of 2009.
The number of overseas trips taken by Irish people increased by 5.9 per cent year on year to 1.77 million. Travel out of Ireland was also affected by the ash cloud and the number of visits fell by more than 120,000 when compared to 2009.
About 2.9 million people visited Ireland in the first half of the year, some 300,000 more than in the same 2010. However, when compared to 2009, when travel was not hampered by the ash cloud, there was a 300,000 drop off.
Tourism Ireland welcomed the improvement in visitor numbers but acknowledged the impact of the ash cloud on the previous year's statistics.
"The current outlook for North America, mainland Europe and emerging markets is positive for the coming months," Tourism Ireland chief executive Niall Gibbons said. "The economic situation in Britain remains fragile and we are keeping the market under close review."
Minister for Tourism Leo Varadkar said the figures suggested the tourism sector was moving into a recovery phase.
"The Government will continue to prioritise tourism as a key industry in Ireland’s economic recovery, utilising the measures contained in our Jobs Initiative," Mr Varadkar said.
“While the figures are a positive indication, we cannot afford to be complacent. With continuing economic uncertainty in most of our key overseas markets, the tourism agencies and the industry will continue to work together to restore sustainable growth to this vital sector."
Mr Varadkar said that by comparison the British tourism market, which was similarly affected by the volcanic ash in 2010, saw lower growth with visits up by only 6 per cent between January and June.
