The largest freshwater lake in Southeast Asia, Tonle Sap is of great ecological and economic importance. It was designated a UNESCO biosphere in the late nineties and is the main source of fish for Cambodia.
This fascinating lake changes in size dramatically twice a year, with its total surface area expanding from 3000 square kilometres to 16000 square kilometres at the start of monsoon season. Monsoon rainfall causes the Mekong River to flood the Tonle Sap with extra water, making it expand in size and depth. At the end of the season the tide turns and the water starts to flow back out and along the Mekong, leaving a smaller, shallower lake behind.
It is also a fascinating cultural destination for visitors who will discover the great floating village of Chong Kneas. As the lake swells in size, the village along the edge of the lake is moved and rebuilt further out, along the new shoreline, while other residents cope with this phenomenon by building floating homes which need re-mooring. Many of the inhabitants of Chong Kneas catch and sell the rich and varied marine life of the lake. A large service industry has also developed. Boat stalls selling fresh produce navigate the 'streets' of brightly coloured homes which make up the village, plying their trade.
The lake itself is, most of the year, large, shallow and placid. It is dotted with fishing boats, speedboats and large 'bus' boats for hire. Glide out towards the centre, away from the busy shoreline, to discover a peaceful stretch of water, bordered by rich green vegetation, fertile farmland and a vast blue horizon.