The Rheinland is one of my favorite places to visit, and I have been there often.  I have driven along the river, cycled it, rode the train, and hiked its vineyard covered slopes.  And finally, after many years, I took one of the boat rides as well.  I have even camped along it multiple times.

The Rhein (English "Rhine") has special lure because of all of the castles packed into one small area.  If you are not sure where to go in Germany, go to the Rhein.  However, there is ONE major drawback:  it is essentially a tourist trap, and thus it is hard to get away from the crowds. 
Mainz to Koblenz
Koblenz to Bonn
One of the best ways to avoid the crowds on the Rhein is to go to castles rarely frequented by visitors.  While I will feature castles visited often, the pages following will also highlight those sites few go to see, or are even aware of.  Put simply, if you wish to avoid the tourist traps, you must go where the tourists don't.

For simplicity, I call the two Rhein sections the Upper and Lower (actually both are Middle Rhein by true definition).  The Upper portion is the most interesting (Upper is determined by being UP river).  It has the most and best of the Rheinland castles.  So come along with me and I'll show you the wonders of the Rhein!
Right, a shot taken inside my VERY hot tent along the Rhein near St. Goarshausen.  I had been cycling all day down the Lahn River and had to stop early due to being pretty tired out!  It was about 4 pm when I took the picture a long time ago (1979). I transformed the photo to grey scale because the color got wacked out due to the sun behind me.  The photo of me above was taken in 2005.



Below are two links, one to the Upper Rhein from Mainz to Koblenz.  The second is for the Lower Rhein from Koblenz to Bonn.  A map below provides a wider overview of the area covered.