At Vietnam’s heritage site Phong Nha, red river carries centuries of legends

The Son River originates in the limestone mountains of Ke Bang and runs underground for more than seven kilometers through the spectacular Phong Nha Cave.

It then merges with the Chay River at the confluence in front of the cave, forming a broad waterway.

About 35 kilometers long, the river serves both as a waterway for visitors exploring Phong Nha Cave and as an integral part of life for generations of people living amid the region's mountains and waterways.

Locals also call the Son River the Trooc River.

On sunny days, the Son River usually runs clear and blue, reflecting the limestone mountains and riverside villages.

This is the familiar image seen by millions of visitors to Phong Nha.

However, these days, the river has taken on a very different appearance, with its waters running a muddy red.

Nguyen Thi Linh, a resident living along the Son River, said that heavy rains upstream in Laos send water rushing down from streams and ravines, carrying soil, rocks and sediment into the river and turning the water a reddish-brown.

After about three to five days without further rain, the river will gradually become clear and blue again.

During the rainy season, from around September to December, the Son River often swells with brown-red sediment flowing downstream.

The unusual color of the water has also inspired people to associate the river's name, ‘Son,’ with several legends about its origins.

Among the stories handed down through generations in Phong Nha is a tragic love story closely linked to the river's name.

According to local lore, long ago, deep in the rugged mountains of Phong Nha, there lived a beautiful young woman from a wealthy and powerful family.

She fell deeply in love with a poor young man.

Her family forbade the relationship, preventing the two from being together.

Yet they remained steadfast in their love and eventually threw themselves into the river, choosing death rather than giving up on each other.

Moved by the sacrifice of the young lovers, villagers named the river ‘Son’ as an enduring symbol of steadfast love.

Another legend tells of a young woman who was abducted by a feudal lord.

She chose death to remain faithful to the man she loved.

After she threw herself from a cliff, water from the surrounding streams poured down and formed a river.

For generations, the Son River has wound gently through valleys like a silk ribbon, depositing fertile sediment, embracing lush cornfields, and bringing fish and shrimp that sustain the riverside communities.