Rothenburg's medieval walls are among the most complete in Germany — a full circuit of defensive ramparts enclosing the old town, punctuated by gates, towers, and timber-roofed walkways that have survived largely intact since the fourteenth and fifteenth centuries. You can access the covered walkway atop the walls at multiple points around the town, and the full circuit takes roughly an hour at an easy pace. The walkway is covered for most of its length, which means it is walkable in rain, and the views out over the surrounding landscape and back down into the tiled rooftops are excellent from every section.
The walls were built in stages and reinforced after the town's expansion in the Middle Ages. The towers and gates each have their own character: the Klingentor at the north end was also a water tower; the Rödertor to the east is the best-preserved and has a museum inside. Some sections were damaged in the Second World War — a single artillery bombardment in 1945, after a US general had already arranged a ceasefire to spare the old town — and were subsequently restored through donations.
Go early in the morning or in the early evening. The walls empty out when the day-trip coaches leave, and in those hours the walkway is quiet enough that you can hear the jackdaws in the towers and the bells from the churches below.