Situated on an Island, Mäuseturm (Mouse Tower) is the only defensive tower and watch-tower in the center of the Rhine, next to Pfalzgrafenstein Castle. The Mouse Tower was built only between 1298 and 1371 by the Archbishops of Mainz. This Neo-Gothic building dates back to the 19th century. With its view of the Mouse Tower, the former park of Landesgartenschau turned the Rhine bank into a cultural bank, a backdrop for a meeting place, a playground, an open-air stage, a park, a museum, a gallery, and an exhibition space, all of them together. I've visited Burg Klopp's tower on the north side of the Rhine, and I walked from there, about 1 mile, and got some close-ups of the tower and the castle ruin (Burg Ehrenfels). It's a straightforward structure not very much to the tower. Unfortunately, there is no access on the island and into the tower unless you kayak or hire a boat. I don't recommend trying to swim the distance (if, fortunately, you were that desperate) so that the moment looks very strong — a lovely place on the beautiful part of the river.