Maldives? Iceland? A painting? No, it's Poland.

Turquoise Lake near Konin. Artificial water reservoir in the place of the former brown coal mine.

The lake was created in the 70s of the twentieth century, when the pit was flooded with water. Waste from power plants was discharged into the lake, and as a result of their mineralization, the water turned turquoise.

Impressive colors from above.