On one of the days that we’re in Cambodia we’ve planned to visit the Tonle Sap–a UNESCO Biosphere Reserve. Yes, UNESCO strikes again!

What’s so interesting about this body of water? Despite having over 400 species of fish, and just as many mammals, birds, and reptiles, the most fascinating feature is the direction of the river flow changes depending on the season. True story.

During the dry season from November to May the Tonle Sap is a tributary of the Mekong. The River flows towards Phnom Penh. In June, heavy rain fall backs up the Tonle Sap and creates a large lake, and water is actually pushed from the Mekong into the Lake. At the end of the rainy season, the River changes direction again.

So, what makes this area worth visiting? (Besides being uber-nerdy?!) Well, the wildlife and scenery, the floating villages and stilt houses to name a few things. The sad part is that we’ll only see the region in the dry season, and not the other extreme. The depth of the lake changes from 1m to 10m during the rainy season. Check out the photo at the bottom of the Peace of Angkor page to see both seasons. We’re actually booked in with Peace of Angkor for the day to visit Beng Mealea and Tonle Sap. I hope it is a good one.