Lines stretching several kilometers were seen outside the monastery on Sunday morning. Believers were waiting with hada, a traditional white scarf, and sometimes cash, which they would present to the monastery.
They would kowtow to a portrait of the "horse-headed king" and wait to be touched on the head by the Vajra Pestle, a sacred instrument in Buddhism.
The annual one-day festival can require long periods of travel to get to the mountainous region.
"I set off yesterday because I wanted to avoid the rush," said an old man waiting in line.
It is believed that celebrating the festival can ward off disaster and hardship in the coming year.