The Mountain-Circling Festival is one of the grandest annual festivals celebrated by the Mosuo people on the banks of the Lugu River in Yunnan. It is a day to pay homage to the holiest goddess of protection - Gemu. On the 25th of lunar July, local people pray for the Goddess' protection by providing offerings to her on the Lion Mountain, which is believed to be the incarnation of Goddess Gemu. Meanwhile, the custom of walking around the mountain is observed.   

The worship of Goddess Gemu by the Mosuo people dates back some 1,000 years. Legend has it that the day of the Mountain-Circling Festival is the birthday of Goddess Gemu, who is beautiful and kind. The Mosuo people honor her as their Goddess of beauty, love and protection. And there's a beautiful story about Goddess Gemu.

One day, Warupuna, her lover of "the walking marriage" comes to spend some time with her. On his way home early in the following morning, his horse falls into the valley and he can't get home before dawn. Then he becomes a statue. Watching the statue, Goddess Gemu's eyes are streaming with tears, which have formed the Lugu Lake. And she becomes the Lion Mountain, protecting local Mosuo people.

On the morning of the festival, putting on their best clothes and carrying offerings, people come to the Lion Mountain to pay homage to Goddess Gemu. They burn incense and kowtow to the Goddess. On the sacrificial ceremony, offerings are presented. After the ritual, people walk around the Lion Mountain, which is customarily called "mountain-circling"; they can also walk around Lugu Lake, which is commonly called "sea-circling".

The mountain-circling festivities last for three days. During the day, activities like singing, dancing, horse racing, wrestling and picnicking are held; during the night, people camp by the Lugu Riverside. This is a good chance for young men and women to get to know each other, so that they could become lovers in the future. 

The Mountain-Circling Festival reflects the importance the Mosuo people on the banks of Lugu River attach to women as well as to the custom of "walking marriage". It is a typical element in the time-honored Mosuo culture.