Roopkund known as Mystery Lake or Skeletons Lake) is a high altitude glacial lake in the Uttarakhand state of India. It lies in the lap of Trishul massif. Located in the Himalayas, the area around the lake is uninhabited and is roughly at an altitude of 16,470 feet (5,020 m) surrounded by rock-strewn glaciers and snow-clad mountains. Roopkund is a popular trekking destination. most popular treks in Uttarakhand