The cycle of Atri, "the guide to A", one of the three main cycles of Dzogchen in the Yungdung Bön tradition. This spiritual treasure was discovered in XIth century by Meu Gongdzö Ritro chenpo, it was organized in eighty meditation sessions; in the XIIIth century, Dru Gyalwa Yungdrung reduced it to a fifteen-session meditative yoga . This practice is very popular among bonpo practitioners thanks to its clear approach; whoever implements it carefully, will experiment the recognition and the stabilization of the Natural State.