Their production tools were simple, made from wood, stone and iron.

And primitive agriculture based on "slash and burn" was the main source of livelihood, besides foraging, fishing and hunting.

In the past 70 years, the Derung have changed. And making stone tools, hunting, carving, and witchcraft－these legacy of thousands of years are dying away.

In 2001, the Derung River township abandoned "slash and burn". And the land is now a forest.

In 2014, 1,068 households in Derung River township moved to new houses built by the government. So, their low-rise, dilapidated houses are now hard to find.

In 2018, the Derung broke away from the poverty that had been their lot for thousands of years.

Today, 5G communication has also reached the Derung River. And not long ago, the Derung River township opened a 5G test base station and became the first township in Yunnan to get 5G.

On April 10, President Xi Jinping wrote a letter to the people in the township, and congratulated them on alleviating poverty. And he encouraged them to "work together to build a better hometown, protect the frontier, and strive to create a better tomorrow for the Derung".