Both. This picturesque glacial stunner is millions of years old. It was formed by a humongous glacier that was scraping down from the Alps, creating a valley in the process. A rocky obstacle made a stand and is still poking its head out in triumph: Bled Island
Another story goes that the lake was once a meadow where fairies used to dance near a big rock in its middle. One day, a fairy got hurt on the sheep-grazed grass. The vengeful fairies called upon the mountain springs to flood the valley, and voilà, a magnificent lake with a fairy island!