After breakfast in Boppard we got in the Opel and drove south along the Rhine. We stopped in Sankt Goar to check out the ruins of the castle, Burg Rheinfels.
Much of the castle is gone, and what's left is largely ruins, but it's quite a setting overlooking the river. I bet they once collected a toll from those who wanted to pass. There is a hotel and a restaurant in the castle but we didn't check out either.