After a lull in the spread of Buddhism in the state during the 10th century, the Tibetan King Yeshe Od of Guge took the initiative to revive it. Of the 21 scholars he had sent to revive Buddhism in the Trans Himalayan region, only two had survived, and one of them was the famous scholar-translator Rinchen Zangpo who transfused Buddhist activity in the state of Himachal Pradesh. Known by the epithet Lohtsawa or the Great Translator, Zangpo built 108 monasteries in the trans-Himalayan region to spread Buddhism, which are considered as the main stay of Vajrayana of Tibetan Buddhism (also known as Lamaism). He institutionalised Buddhism in this region. Zangpo had engaged Kashmiri artists who created wall paintings and sculptures in these legendary 108 monasteries; only a few of these have survived in Himachal Pradesh namely, the Lhalung Monastery, Nako Gompa in Spiti and Tabo Monastery in Spiti, the last named monastery is known as the Ajanta of the Himalayas. In Himachal Pradesh, apart from these ancient Buddhist monasteries set up by Zangpo, his contemporaries of other Buddhist sects built many more monasteries. This activity thus further continued in the subsequent centuries under the four main traditions of Nyingma, Kagyu, Gelug, and Sakya, categorised as per teachings into three vehicles:Hinayana, Mahayana, and Vajrayana. These monasteries are mostly in the Spiti, Lahaul and Kinnaur valleys. Some of the well known monasteries are Gandhola Monastery (Drukpa Kargyu sect) Guru Ghantal Monastery, Kardang Monastery (Drukpa sect), Shashur Monastery, Tayul Monastery and Gemur Monastery in the Lahaul Valley, Dhankar Monastery, Kaza Monastery, Kye Monastery, Tangyud Monastery (Sakya sect), Kungri Monastery (of the Nyingma sect), Kardang Monastery (Drukpa Kagyu sect) and Kibber Monastery in the Spiti Valley, and the Bir Monasteries (Bir Tibetan monasteries of the Nyingma, Kagyu and Sakya sects) in the Kangra valley.