On Yuan Chwang's Travels in India, 629–645 A.D. v1.c12.s2.5

v1.c12.s2.5

With reference to this Monastery we read that the Buddha accompanied by the faithful yaksha Vajrapāṇi passed over a dark green wood on his way through the air to convert the Dragon-king Apalāla. Addressing the Yaksha Buddha prophesied that in that place 100 years after his decease a vihāra would be erected to be called “Darkness-wood” which should be preeminent for absorbed meditation.³