São Francisco River
The Yukon River is a major watercourse of northwestern North America. The source of the river is located in British Columbia, Canada. The next portion lies in, and derives its name from the Yukon Territory. The lower half of the river lies in the U.S. state of Alaska. The river is 1,980 miles (3,190 km) long and empties into the Bering Sea at the Yukon-Kuskokwim Delta.
The Murray River is Australia’s longest river. At 2,375 kilometres (1,476 mi) in length, the Murray rises in the Australian Alps and, for most of its length, meanders across Australia’s inland plains before reaching the ocean at Lake Alexandrina.
The Mackenzie River is the largest river system in Canada. It flows through a vast, isolated region of forest and tundra entirely within the country’s Northwest Territories, although its many tributaries reach into four other Canadian provinces and territories.
The Mekong is a river in Southeast Asia. It is the world’s 12th-longest river and the 7th-longest in Asia. Its estimated length is 4,350 km (2,703 mi), and it drains an area of 795,000 km2 (307,000 sq mi), discharging 475 km3 (114 cu mi) of water annually.