if you mean River Thames, the source is Thames Head in Gloucestershire
The River Thames is 210 miles long from its source in the Chiltern Hills to its estuary at the North Sea.
Answer!-Usually the start of a river is called its source and the end of the river is called the mouth.
The source of a river is where the river starts.
river themes
The source or beginning of a river is called the 'headwater'. The beginning of a river is known as the source.
The place where the river begins is called a source.
the sun
the river yellow source is china
The source is where a river begins. The end of a river is usually at the sea.
he Source of a river is the start of the river. It's often found in the mountains.
The Meander comes after the River Source
Exe Head is the source of the River Exe.