The Son River is about 7,729 meters/4.8 miles long upstream and runs underground beneath the limestone mountains in Phong Nha-Ke Bang National Park. As a tributary of the Gianh River, it’s located in the northcentral coastal region in Quang Binh Province and flows towards the shore where it empties into the South China Sea.
The river’s other name, Song Troc, translates to “lipstick river” because of how red the water gets during the flooding season. According to legend, the river’s name honors a couple whose families forbid them to be together romantically, leading them to commit suicide in the water. Despite this sad story, the river is one of the most beautiful and pristine ones found in this area of Vietnam.
Driving towards Phong Nha, the river often has a stunning blue color as it wraps itself around some of the most amazing natural views of cornfields and banana trees. The mountainous vistas surrounding this river offer incredible photography and peaceful sightseeing opportunities.
Activities by the Sông Son (or Sông Tróc)
While Son River isn’t the biggest one in the country, it’s situated in a popular spot for a few nearby activities.
Oxalis Cave Tours
The Oxalis company offers a few different cave tours in the Son River’s underground areas. There are multi-day trips, family trips, team building tours, and even tours of the famous Son Doong, the world’s largest natural cave. Doing an organized tour like this one ensures that you’ll get to see a unique side to the river that many don’t.
Phong Nha Cave Tour
The Phong Nha Cave Tour is a must-do activity for anyone visiting this part of Quang Binh Province. After seeing Paradise Cave, the longest dry cave in Asia, visitors get to eat lunch and take a 25-minute boat ride on the Son River to see the Phong Nha Cave. The group is allowed a couple of hours to explore the inside before heading back to town. The entire adventure takes an entire day, roughly nine hours in total.
The Son River is great for swimming in, but only at certain spots in Phong Nha. One of the best beaches in town is located behind the Oxalis Phong Nha office, which is free of charge for people who take one of their tours. It’s an open space with fantastic natural views, a cafe and drink service, and no extra cost to use.
Stay at a Vacation Rental
To experience more of the beautiful outdoors in the Phong Nha region, book a stay at a vacation rental along the Son River. One of the most popular properties, the Son River House, offers accommodations with free WiFi, private rooms and bathrooms, breakfast buffet options, and comfortable beds with fantastic river views.
Address: Quang Binh Province, Central Vietnam
Hours: 24 hours