"Thousand two hundred years after the Buddha, the Teacher Padma Sambhava brought the Blessed One's teachings closer to the earthly ways. .... Padma Sambhava did not die, but left to teach new countries. If he did not leave, the world would be in danger."
"In the cave of Kandro Sampo, near Tashiding, close to hot springs, there was the home of the famous Padma Sambhava .... And now, in the cave, there is an image of Padma Sambhava, and behind it, there is a stone door. It is known that the Teacher concealed behind this door some sacred secrets for the future, but their time has not yet come."

N.K. Roerich. Altai – Himalayas.

During a trip to the monasteries of Sikkim, the Roerichs could visit the Khadro Sangphug Cave where, according to a legend, Padmasambhava meditated with his wife. Around the cave, there are hot springs; they arose after Guru Rinpoche defeated the Raksasi, who dwelled in this cave. It is also claimed that Padmasamhava hid in the cave the Torma (sacred texts and statues), which will be found when their time comes.
In Sikkim, Nikolay Konstantinovich found a rare thangka "The Acts of Padmasambhava", and the Roerichs decided to purchase it. The painting was made in a technique close to Tibetan paintings, both in style and color. The image of Guru Rinpoche itself was also canonical. However, the landscape of the picture, in such details as the waterfall, springs and mountains, corresponded to the vicinity of the Khandro Sangpug Cave. The artist painted a scene of the Teacher's conversation with a gigantic mountain spirit, as drawn on the thangka.
"A certain giant decided to build a passage to Tibet and tried to get into the Holy Land. Then the Blessed Teacher got up, rose in height and struck the bold adventurer. So destroyed was the giant."

N.K. Roerich. Altai – Himalayas.