What is Spiti valley famous for?

Spiti valley is acclaimed for its distinctive Moon-esque landscapes and interesting landforms. 5 entities that define the Spiti valley are: 

• Chandratal —.the lake of moon.  
• Buddhist monasteries of Ki, Kaza, Kungri, and Tabo. 
• Snow leopards of Kibber —  the grey ghost of the Himalayas.
• Fascinating Tibetan culture and customs. 
• Fossils — dating back to the Triassic period (252-201 million years ago) — of  Langza village.