the Mississippi headwaters is a kind of thing that is located in the Mississippi river. The Headwaters of a river are it's origins. The multiplicity of small streams that converge to form the main body of the river proper.
Lumber river
The source of river is known as its headwaters. In the example of the Mississippi River, its headwaters is Lake Itasca in Minnesota.
Mississippi
headwaters
The "source", or its "headwaters"
The Meander comes after the River Source
The headwaters of the Brahmaputra River can be found in Tibet, China, where it originates as the Yarlung Tsangpo River. The Mekong River also has its headwaters in Tibet, specifically in the Tibetan Plateau, where it is known as the Lancang River before flowing through several Southeast Asian countries.
It is the source, or the headwaters.
Pennsylvania
Headwaters of the Amazon River
Mississippi