Tibetans snuck into India dodging Chinese border guards to see their spiritual leader, the Dalai Lama, perform the 33rd Kalachakra for world peace in Shey, a tiny town nestled 3,400m-high in the Himalayas.
The massive religious teaching, said to empower tens of thousands of his disciples to attain enlightenment, is a significant event for Buddhists.
About 150,000 devotees from around the world are flocking to the northern Ladakh district in India-administered Kashmir, which shares an eastern border with Tibet.
The Dalai Lama also reiterated his plea to Buddhists in Myanmar and Sri Lanka to halt violence against Muslims, in a speech to tens of thousands of devotees to mark his 79th birthday.
China reportedly deployed extra troops and cracked down on Tibetans travelling to attend the 12-day gathering that began on July 3. Despite this, several Tibetans told Al Jazeera that they crept over the border at night.
The Dalai Lama fled China in the 1959 Tibetan uprising against Chinese rule, settling in Dharamshala in northern India, where he set up the Tibetan government in exile. He has since held Kalachakras every few years or so around the world - from India to New York.
The Tibetan spiritual leader remains a point of tension between India and China. Just days before the Kalachakra, Chinese troops reportedly showed their might at a disputed border between Tibet and Ladakh, repeatedly entering territory both countries claim.