Science Notes Rubrics List Home Lesson 2 . . The place where a river begins is called its source .
Rivers begin high in the mountains, where melting snow gathers in small streams.
The water winds its ways through alpine meadows and begins its downward journey. This picture shows a young river flowing in its stony bed. The water twists this way and that around the rocks. The young river flows swiftly, with many rapids and waterfalls. It erodes its bed and cuts a narrow, V-shaped valley with steep sides.