These are Naga Boats (other cultures call them Dragon Boats). The naga are snake creatures which live under the water. When the Buddha was in meditation to seek the Middle Path, a thunderstorm blew up and the Seven Headed Naga King flared out his heads to protect the Buddha. Many communities along the river worship the naga and at the end of Buddhist Lent, have races so the naga can enjoy the activities of humans.
This race took place in Salavan in October 2008, along the Xedon River which flows into the Mekong at Pakse.
There are still few roads in many parts of Laos, so a lot of good are shipped by boat. People live on the boats - and there's always the need to do laundry.
Boat at sunset along the Mekong.
This is my contribution to Photo Hunt.
