These Countries Topped Europe's Rankings For The Cleanest Lakes And Rivers In 2025

From Northern Italy's heaven-sent lake district to the 700-plus Blue Flag beaches of Spain, and the legendary fjords of Norway down to the surf-bashed coast of Portugal, Europe is peppered from head to toe with tempting swimming locations. And it's not just the variety and beauty of it all that'll have you donning speedos on your European vacation this year — it's the cleanliness, too. A 2024 survey headed up by the European Environment Agency (EEA) has concluded that most of Europe's bathing waters are of pretty darn high quality.

After checking a nearly 22,000 individual bathing sites across the continent for the presence of various bacteria, it turns out that a whopping 85% of all monitored sites met the highest standard of all. That said, when it came to inland spots like rivers and lakes, there was a slight dip in the number of top-rated locations. Nonetheless, it also emerged that only a few nations that scored a perfect 10, offering the cleanest noncoastal waterways out there, while others managed excellent ratings at an enviable 95% or more sites.

They're some seriously alluring places, too. Just to whet the appetite, you'll have the pick of mountain-shrouded alpine lakes, glacier-fed rivers, and even inland swimming spots in otherwise beach-heavy destinations surrounded by the sun-kissed Mediterranean Sea. So, read on if you're keen to swap sands for lakesides this season and enjoy some of Europe's cleanest H2O while you're at it.

Bulgaria tops the bill with a 100% excellence rating across all its inland waters. That's the same as other countries below, you say? True, but Bulgaria has the added distinction of having tested multiple sites as part of the study. Indeed, four different swimming spots were monitored, which gives the home of shopska salads and onion-domed churches a bit more in the way of bragging rights compared to its peers.

In the proverbial spotlight was the utterly idyllic Pchelina Reservoir. Also known as Lake Pchelina, it's a highland escape set just over an hour's drive outside of Sofia. Hemmed in by swathes of woodland and hills, it is watched over by a haunting little chapel that commands a fine view of the whole lake. The water — the clean, clean water — is often used by kayakers, who can sail below said chapel and paddle through bird-filled marshes to boot.

The Studen Kladenets Reservoir also ranked as excellent. You'll need to head to southern Bulgaria to find it, tucked away between the peaks and troughs of the Rhodope Mountains, where it supports rare wolf and deer habitats. The site has also recently been the focus of a rewilding campaign that now means you can come to spot a herd of European bison living on the banks.

Greece is a veritable heaven for swimmers of all sorts. Some of the best beaches on the planet await here, running the gamut from mountain-backed Paleokastritsa in Corfu to the blazing white sands of Navagio Beach in Zakynthos. What's more, the land of saganaki and spinach pies has the second highest number of Blue Flag spots on the globe, and its inland waters were lauded in the EEA's recent study.

That said, only one solitary inland swim spot was looked at in Greece: Lake Vouliagmeni. It hides along the side of the glamorous Athenian Riviera, a region currently making a comeback, a 40-minute drive south of the heart of the capital. Not actually a lake at all, but rather a cleft in the cliffs that's been submerged by a series of natural springs, it's the site of a chic spa and wellness resort that features exclusive sunning decks and a fusion restaurant — not to mention a rather hefty entrance fee of about $22 on weekends.

If your travel budget can't take that sort of hit, consider visiting Crete. It's the largest isle in Greece and comes with a side of fantastic freshwater swimming locales. They range from gorgeous Lake Kournas, where you can pedal under the gaze of the island's great mountains, to the hidden oasis and waterfalls of the Kourtaliotiko Gorge.

Romania was another 100% excellent scorer when it came to the quality of inland water bathing in the EEA's study. But, like Greece, that accolade was based on data from just a single spot. Cue Lacul Ciuperca. A favorite freshwater stomping ground in the town of Tulcea, it's nestled right beside the Saint George Branch of the Danube as it begins its long journey through the wild Danube Delta toward the Black Sea.

A series of significant redevelopments in the 2000s saw the transformation of Lake Ciuperca into the R&R hub of Tulcea and the greater region. Not only was the lake deepened, but man-made beaches, sports facilities, and multiuse paths were also added to the surrounding shores.

The good news is that it's certainly not the only thing on the menu for lovers of all things Romanian lakes. Just check out the Ochiul Beiului Lake. It may not have been looked at during this particular study, but it's otherwise famed for its gleaming teal color and prime location deep within the forests of Nera-Beusnita National Park. One past visitor summed it up on TripAdvisor as follows: "This small lake has some of the amazing blue/green colors I have ever seen. With some imagination and good eye, a photographer might take amazing photos."

Last, but most certainly not least, comes yodel-echoing Austria. In many ways, this is the most remarkable addition to this list, since the land of schnitzel and strudel emerges with a tantalizing rating of 95.8% excellence across its many bodies of water. The keyword there is "many" — a whopping 249 individual inland bathing spots were tested here, which is a load more than anywhere listed above.

Among them, you'll find some big hitters. There are multiple sites around the shores of Zell am See, for example. That's a real stunner, drawing over a million people each year with the promise of quintessential alpine enjoyments — from meadow walking to boat trips and hiking below the tallest mountain in the country in the nearby Hohe Tauern National Park.

Lake Hallstatt, home to the ultra-gorgeous gingerbread village of the same name, is also there. It's often said to be more fjord than lake, what with soaring peaks jutting overhead. You'll want to stick to the beaches and bathing islands below if you're keen to get into the water, though.