This lake is an endorheic lake in the Himalayas situated at a height of 4,350 m. Its circumference is 134 km, and its maximum width is 5km. The lake passes through the India-China border and requires an inner line Permit for travel from Leh, which is a five-hour drive. The lake entered into popular culture when it was the site for the final scene in the Bollywood blockbuster Three Idiots. Name the lake.