A mountain valley in Shuanghe Village of Dali City in southwest China's Yunnan Province sees an "eruption" of numerous beautiful butterflies in the summer of each year, enabling the valley to earn the nickname as the "Butterfly Valley".

Since the shut-down of some private small coal mines in the local region 20 years ago, the ecological environment in the vicinity has significantly improved, paving the way for the butterfly booming.

Beginning from May 2000, the breeding of butterflies in the15-kilometer-long valley has kept increasing.

As the environment getting friendlier, a great deal of butterflies would flock to the valley each summer, and in particular, the number of butterflies observed in the valley so far this year appears to have peaked.

The numerous butterflies fluttering colorful wings just make a natural wonder in the valley and beyond.

The Butterfly Valley is famous for the jade-like white butterflies with stripes. The Butterfly Valley is home to many species of butterflies of varying sizes and of various colors.

Like little elves, the dancing butterflies make a beautiful view in the summer.