High Quality Content by WIKIPEDIA articles! The Phobjika Valley (also spelt Phobjikha, the suffix kha means valley in Dzongka) is a vast U-shaped glacial valley, also known as Gangteng Valley named after the impressive Gangteng Monastery of the Nyingma sect in central Bhutan, where the graceful Black-necked Cranes in Bhutan (Grus nigricollis) from the Tibetan Plateau visit the valley during the winter season to roost. On arrival in the Phobjika Valley in the last week of October, the Black-necked Cranes circle the Gangteng Monastery three times and also repeat the process while returning to Tibet.:152–154