Mount Nyiragongo is an active volcano in Virunga National Park, Democratic Republic of the Congo. Trekking to the crater rim (starting at 1,989m/6,525ft, reaching 3,470m/11,380ft) is about 5-6 hours, the hikers sleep in huts on the top and enjoy stunning night views of one of only several crater lakes in the world, this one being the largest.