The Massa () is a seven kilometre long river in the eastern Bernese Alps in the Swiss canton of Valais. It is mainly fed by the melt-water from the Aletsch Glacier. It passes through the Massa Gorge and flows into the Stausee Gibidum reservoir and onwards to its confluence with the Rhône. The whole area, including other glaciers is part of the Jungfrau-Aletsch Protected Area, which was declared a UNESCO World Heritage Site in 2001. See also List of glaciers Retreat of glaciers since 1850 Swiss Alps References The Massa on the National Map of Switzerland Massa Rivers of Valais