Have read that they say it's better to do upstream.
I travel real light. Did a two weeks winter trip with approximately 15l.
Along Danube River, there are lots of Bread & Breakfasts just beside the cycling path that cater to cyclists.
Sho all chiu really nid is a credit card and minimal clothing.
Bicycle touring (Radfahren) ish really popular in Germany and Austria.
When I cycled along River Danube 15-20 years ago, met lots of grandpas and grandmas cycling with picnic baskets on the front of their bikes. When they got tired, they just stopped along the riverside and laid out their picnic mat. They were very generous as they offered to share their french loafs, cheese and wine with me. As you travel along the Danube, you'll tend to meet the same few families, who are going in the same direction as you are, at the various towns along the way so it's easy to find good company.
Also came across lots of German families with toddlers that cycled along that route.
Hope you go during the apple season cuz there are lots of apple tress in those valleys.
Certain towns like Vienna, Prague and Budapest have cobblestone roads and those can be quite uncomfortable to cycle in. Also, do beware of tram tracks and remember to cross them at 90 degrees. Not fun when chiur front wheel gets caught inside that groove.
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