The most famous spot inside Durmitor is Black Lake, or Crno Jezero in Montenegrin. It looks dark from above because the tall fir trees around it reflect into the water, turning it a deep green-black. In winter the lake freezes and the snowy peaks behind it glow pink at sunrise - visitors say it looks like a painting.
Durmitor has 18 glacial lakes, all formed when enormous glaciers ground across the rock thousands of years ago and scooped out hollows that filled with water when the ice melted. The park also has karst - a type of landscape where rainwater has dissolved the limestone over millions of years to create caves, pits and strange rocky towers.
The forests of Durmitor are some of the oldest in Europe. Some of the black pines here have been growing for more than 400 years - they were already tall trees when Christopher Columbus first crossed the Atlantic. Bears, wolves and the extremely rare Balkan lynx all live inside the park, hidden among the ancient trees.