The Crescent Lake's water is so pure and sweet that it looks like an emerald set in the sand

  Located approximately 6 km (3.73 miles) from the outskirts of the city of Dunhuang in Western China, lies Crescent Lake, an incredible oasis in the Gobi desert. Known as Yueyaquan in Chinese, the crescent-shaped lake is a major tourist attraction where one of the world’s great shrines to Buddhism resides.

  The Crescent Lake's water is so pure and sweet that it looks like an emerald set in the sand. Many of the visitors who have made their way down the mountain like to drink from the lake. According to historical record, the lake has been in existence for hundreds of years without ever being buried by the sand; it is really a geological wonder.
  There is also a story about the lake. In the Western Han Dynasty (206 BC - 24), a general called Li Guang, together with a group of soldiers, captured a powerful and swift horse from Dawan, a western state of China at that time. When passing the Echoing-Sand Mountain upon their return, the soldiers became too thirsty to continue their march. General Li drew his sword and thrust it into the side of the mountain causing water to spring forth and so formed the lake.