During your trip to Laos, I encourage you to explore the Nam Ou's beautiful surroundings, whether you are coming from the north of the country, for example from Muang Khua towards Nong Khiaw, or whether you are going upriver from Luang Prabang.
Nam Ou is overlooked by some impressive cliffs, and I took the opportunity to go and explore the hundreds of statues of Buddha you can find in Pak Ou cave, north of Luang Prabang.
I also enjoyed spending a few days in Nong Khiaw, and also the even more peaceful village of Muong Ngoy. On the way, the pirogues coming and going, little fishing boats and the magnificent sun sets over the mountains have left me with some wonderful memories...
Travelling down the River Nam Ou during summer was a highlight of my trip to Laos. You're plunged straight into a magnificent, savage paradise.
The river is bordered by jungle and mountains, home to numerous ethnic communities such as the O'Pa and Si La. If the boat stops en-route, take the time to visit some of the villages. Laotians are very welcoming and curious to meet foreigners. I do advise you to remain respectful of the villagers and their customs. Don't be intrusive and only strike up a conversation if they show interest.
Going down the rapids on the river involves getting soaked and you may need to get off the boat if the water level's low...but the adventure's well worth it!