Khonephapheng waterfall in Southern Laos Sipandone area

The Khonephapheng waterfall (Lao: ຂກົກນເກະ ຜກະ ຜເກະງ) is located on the Laotian part of the Mekong River in the Southernmost province of Lao PDR - Champassak.

The Khonephapheng waterfall are closed to the border of Cambodia.

The Khonephapheng waterfall is the main reason, why the Mekong river is not navigable into Thailand, Burma and China.
The French colonialists made in the late 19th century several efforts to make the falls navigable but all failed.
The only successful attempt by the French was made possible by building two ports, one in the South of Khone Island (below the falls) and one in the Eastern shore of Det island (above the falls), linking the two islands with a bridge and connecting the two ports with a small railway. By doing so, the French were able to circumvent the steepest rapids and allow trans-Mekong-shipment.

The total height of the Khonephapheng falls is 21 meters in several cascades stretching over 10 kilometers of the Mekong river's length. The average discharge of the cataract is nearly 11,000 cubic meters per second, making the Khonephapheng falls the largest waterfall in terms of volume in Southeast Asia.