Fresh, never frozen
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An alpine forest's brilliant green palette is the perfect complement to the aquamarine tones of Lake Zelenci, but the water's intense color isn't limited to the verdant summertime. Since it's fed by a natural underground spring, which bubbles up through the Swiss-cheese lakebed flecked with tiny holes, the lake keeps a fairly constant temperature of just above 40 degrees Fahrenheit. Thus, even in the harshest Slovenian winters, these painted waters never turn to a blank canvas of ice.