Guess the locations where major rivers start. This can be a confluence, lake exit or small stream.
This map consists of places where major rivers start, whenever there is streetview available nearby. Zooming, navigating and using google and the internet is allowed. Navigation is impossible in many remote area's.
There can be multiple sources, sometimes disputed. In general, the widely accepted source is choosen. This is not always a small stream, but it can also be a confluence or lake exit.
Take note: extreme difficulty due to remote places!
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