A legendary tantric master, Padmasambhava is the father of the Nyingma School of Tibetan Buddhism, to which Rongbuk Monastery belongs. Stories about his travels throughout the Himalayas, and the sites where he tamed and converted local spirits are considered sacred. One such episode takes place in the Rongbuk Valley, where Padmasambhava defeated the practitioners of Bon, Tibet's indigenous religion. When a Bon lama accosted Padmasambhava with his magical drum on Everest's peak, the lama perished. Now when the rumble of an avalanche is heard, locals say the spirits are beating the lost drum.