MNN Galleries

13 of the most bizarre lakes in the world

By: Bryan Nelson on Sept. 13, 2010, 11:36 a.m.
In addition to floating villages, Tonlé Sap is a wealth of biodiversity.

Photo: Aleksandar Todorovic/Shutterstock

12 of 15

Tonlé Sap

The unique ecosystem of Cambodia's Tonlé Sap evades classification as either a lake or a river.

During the dry season, the waters of the Tonlé Sap drain into the Mekong River, but during the monsoon season the flow of water is so massive that it actually pushes back up from the Mekong, forming the largest freshwater lake in Southeast Asia. This lake is particularly unusual for the fact that its flow violently changes direction twice a year.

Because of these bizarre conditions, the region is a treasure trove for biodiversity and it has been designated a UNESCO biosphere.