Black lake.

As the crown jewel of Durmitor National Park’s 18 glacial lakes, Black Lake (Crno Jezero) delivers dramatic alpine scenery with remarkably easy access. Sitting just three kilometers from Žabljak, this high-altitude wonder is actually two distinct bodies of water—Veliko and Malo Jezero—connected by a narrow strait. The lake gets its signature ink-blue, almost black hue from the deep waters of the smaller basin and the shadow of the dense pine and spruce forests hugging the shoreline. Framed by the stark limestone peaks of the Durmitor giant, it is a magnet for low-key outdoor recreation. Visitors can tackle the gentle 3.5-kilometer loop trail that circles the water, rent a kayak in the summer, or use the lake as a scenic springboard for more demanding treks deeper into the UNESCO-listed park.