Siddhashrama
In Hindu theology, Siddhashrama is a secret land deep in the Himalayas, where great yogis, sadhus, and sages who are siddha live. The concept is similar to Tibetan mystical land of Shambhala.
Siddhashrama is referred in many Indian epics and Puranas including Ramayana and Mahabharata. In Valmiki's Ramayana it is said that Viswamitra had his hermitage in Siddhashrama, the erstwhile hermitage of Vishnu, when he appeared as the Vamana avatar. He takes Rama and Lakshmana to Siddhashrama to exterminate the rakshasas who are disturbing his religious sacrifices (i.28.1-20).
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