While it ranks as the seventh longest river in Asia, the Mekong is known as the "Mother River of Southeast Asia," sustaining civilizations throughout the centuries.
As the Mekong descends from the Tibetan Plateau through China's Yunnan province, Myanmar, Laos, Thailand, Cambodia and Vietnam, it reveals itself as one of the richest areas of biodiversity on the planet.
In 1995, Laos, Thailand, Cambodia and Vietnam created the Mekong River Commission to assist in the management and coordinated use of their shared vital artery.
Among the international companies that have Mekong river cruise offerings are Avalon Waterways, Viking River Cruises and AmaWaterways.
My Tho, 45 miles southwest of Ho Chi Minh City, is the economic heart of the Mekong Delta and the embarkation port for northbound cruises and the terminus on southbound itineraries that originate in Cambodia.
Avalon Waterways offers a seven-night cruise between My Tho and Cambodia's Siem Reap aboard the 36-passenger Siem Reap. Because of its intimate size and shallow draft, it is able to sail all the way to Siem Reap for at least half of the year, rather that embarking/disembarking passengers at Kampong Cham, Cambodia.
Siem Reap is home to the Unesco World Heritage Site of Angkor Wat. Dating to the early 12th century, the temple complex was first Hindu, then Buddhist, and is the largest religious monument in the world.
Viking River Cruises, which operates the world's largest fleet of river cruise ships, sails its Viking Mekong between My Tho and Kampong Cham. Refurbished in 2013, the Viking Mekong accommodates 56 guests with river views from every stateroom. Motorcoaches connect Siem Reap with Kampong Cham.
AmaWaterways operates two Mekong ships: the 92-passenger La Marguerite and the 124-passenger AmaLotus. Both are operated between My Tho and Kampong Cham with motorcoaches connecting Siem Reap with Kampong Cham. The company recently announced that its new, state-of-the-art vessel, the AmaDara, will make its inaugural sailing on the Mekong on Aug. 17, 2015.