The vast majority of Europe's beaches offer "excellent" water quality for swimming, the EU environment agency said on Tuesday ahead of the summer season, with coastal nations and inland Austria topping the list.

"This summer we can all reap the benefits of solid implementation of EU bathing water rules, which have made a vast majority of our bathing waters clean enough to swim in," the director of the European Environment Agency (EEA) Leena Yla-Mononen said in a report published Tuesday.

More than 85 percent of bathing sites across the European Union had "excellent" water quality, with Cyprus, Bulgaria, Greece, Austria and Croatia standing out with at least 95 percent of their sites classified as "excellent".

Water quality can be classified as "excellent", "good", "sufficient" or "poor", depending on the level of detected faecal contamination.

Polluted waters can, if ingested, cause illness, including gastrointestinal problems and diarrhoea.