The boat docks on the Neckar River somewhat downstream from Heidelberg and buses take us the rest of the way. It's a time-saving gimmick: the boat is slow compared to buses; while we're touring Heidelberg castle and its town, the boat can complete the trip to Speyer and we'll be that much further along.
Heidelberg is impressive, but much less so than I had expected. In that sense, I guess, it was a disappointment for someone who has watched The Student Prince once too often.
No pictures here, alas. Viking River Cruises' free Wi-fi is worth every penny I paid for it -- uploading anything is next-to-impossible.