In the valleys of the east cental Black Forest of Germany arise two small rivers: The Breg and the Brigach. They come together to form the Donau (German for Danube) on the one-time estate of the Fürstenburg Counts called Donaueschingen.
This confluence, the official source of the Danube, is in view of a bridge over the river carrying Federal Highway (Bundesstrasse) 27 southward out of Stuttgart, heading toward the Swiss border.
The source of the longer of these two small rivers, the Breg, begins as a little brooklet emerging from under a headstone at the upper, western, end of a picturesque valley that features an inn and restaurant, and a small chapel nearby. You reach this point on a narrow road that clings to the north side of the valley; a fifty metre path leads down to the source itself, where you can dip your hands into, and sample, the furthest source of one of the two great storied rivers of Europe.
Interestingly, the other river, the Rhein, is not far away, despite the fact that it empties eventually into the North Sea. So the continential divide between the Black Sea (& Mediterranean) and the North Sea, snakes its way across southern Germany, quite close to both rivers.
During the Ice Age, the Rhine in Germany and the Thames in England were the same river. They were connected over what is now the English Channel.
Awesome. You ought to write travel books. Do you have any photos to post?