Dublin's north inner city was the country's biggest litter blackspot last year, according to the final survey of 2019 by business group Irish Business Against Litter (IBAL).
The area was described as 'seriously littered' and ranked at the bottom of 40 neighbourhoods across 27 towns and cities surveyed for cleanliness - its worst ranking in years.
The survey, conducted by An Taisce, found "the dearth of clean sites in this area was striking".
"Dumping was evident in the worst sites, among them Aldborough Place, Crinian Strand, Great Clarence Street North and North Strand Road."
By contrast, Dublin city centre was found to be much cleaner, according to An Taisce.
It praised the popular tourist attractions of Christ Church Cathedral, Trinity College, the Guinness Storehouse, Garden of Remembrance and main shopping streets as "excellent" for being litter-free.
However there were also litter blackspots in some areas of the city centre, including Loftus Lane in Dublin 1, where old mattresses, microwave ovens and other domestic waste was found dumped.
The north county Dublin community of Swords ranked third on Ireland's litter-free list and was described as 'a model for others to follow," whereas Tallaght in south county Dublin was found to be 'moderately littered."
Ballymun was also found to be littered but had improved on previous years.
Overall, Kilkenny city took the top spot as the cleanest town in Ireland.
While IBAL found that there was 'significantly less' litter on our streets last year compared to a decade ago, with a decline of about 13pc, the discarding of food and sweets wrappers, gum and cigarette butts on streets remains a problem.
"We've seen the fruits of the greater attention given to keeping our city centres clean, to the point where they are now almost as clean as our towns.In 2019, for the first time, all were deemed clean," said IBAL spokesman Conor Horgan.
However, he said there has been no noticeable decline in litter in disadvantaged areas of cities over the past five years.