The sunset is seen at the Whistling Dune Bay in Dalad Qi in Ordos, north China's Inner Mongolia Autonomous Region, July 15, 2016. Located in the east of Kubuqi Desert, the Whistling Dune Bay was developed as a tourist destination since 1984. After years of improvement, it became a landmark for tourism industry of the Inner Mongolia Autonomous Region. Photo: Xinhua

The path and a starting point for camel safari are seen at the Whistling Dune Bay in Dalad Qi in Ordos, north China's Inner Mongolia Autonomous Region, July 15, 2016.Photo: Xinhua

A path is seen from above at the Whistling Dune Bay in Dalad Qi in Ordos, north China's Inner Mongolia Autonomous Region, July 15, 2016. Photo: Xinhua

A tourist train runs at the Whistling Dune Bay in Dalad Qi in Ordos, north China's Inner Mongolia Autonomous Region, July 15, 2016. Photo: Xinhua

A tourist site is seen at the Whistling Dune Bay in Dalad Qi in Ordos, north China's Inner Mongolia Autonomous Region, July 16, 2016. Photo: Xinhua

The starting point of sightseeing vehicles is seen at the Whistling Dune Bay in Dalad Qi in Ordos, north China's Inner Mongolia Autonomous Region, July 15, 2016. Photo: Xinhua

Sand dunes are seen at the Whistling Dune Bay in Dalad Qi in Ordos, north China's Inner Mongolia Autonomous Region, July 15, 2016. Photo: Xinhua

Silhouettes of tourists are seen on sand dunes at the Whistling Dune Bay in Dalad Qi in Ordos, north China's Inner Mongolia Autonomous Region, July 15, 2016. Photo: Xinhua