German motoring club ADAC runs reliable tests each year on water quality and pollution in the seas around Europe. Recently it announced that the Croatian part of the Adriatic Sea - the gorgeous island-sprinkled Dalmatian Coast - is the cleanest part of the entire Mediterranean, with no large-scale pollution and high water quality.
It reminds me of just last summer, when I drove down the coast of Croatia, stopping frequently to swim in that perfectly clear turquoise sea. If you're still planning your European summer and you want to enjoy the clean sea, check our article on Dubrovnik; or head far north to the Baltics to some of our other favorite coastal spots, the Curonian Spit in Lithuania or the islands of Estonia.