That stretch of the Neckar has several castles including the huge old Heidelberg Schloss. You can get to most of them by catching an excursion boat right in front of the hotel. When we got there we were shocked to find the Zum Ritter closed due to fire damage. I hope it will be rebuilt so we can stay there again some day.
The day we were there was a holiday so we had a hard time finding accommodations for the night. We ended up at The Gruner Baum in Neckargerach, a small town nearby. It was a pleasant place and we had a good time wandering around the neighborhood before having dinner on the veranda of the hotel.
...The Neckar from the Weinstube next door.... One of the excursion boats that ply the river.
....The Gruner Baum in Neckargerach.....Us having wine on the veranda.