Temps went down to the mid 40's overnight, but recovered to sunny and 65.
We decided to pass on the Marksburg Castle climb and walked a bit of Koblenz on our own. Its important geographic feature is the Deutschen Eck, the confluence of the Rhein and the Mosel. We saw the statue of Wilhelm the First as well as the Berlin Wall recognition and memorials to the Jews who were deported and murdered.
The rest of the day (and night) were spent cruising the Rhein, into the Main via numerous locks. (There are 67 from beginning of cruise to end.) As we sat on the sun deck watching the vineyards and castles go by, Kane, the cruise director, provided commentary.
The bar staff showed how to prepare a local coffee/brandy drink and then we had Brotzeit (again) which is any opportunity to eat.
The sun deck was lowered so that we can pass under the old bridges we encounter.
Dinner was cheese and spinach canneloni or grilled jumbo shrimp; desert was lime cake.