The Wetterau is a broad, fertile basin north of Frankfurt, and the Limes crosses it on its way from the Taunus hills towards the Main. Near Butzbach, the frontier runs through farmland and low wooded ridges, with a line of watchtowers, and the stretch between towers 4/37 and 4/39 is a quiet piece of it. The Saalburg, the reconstructed Roman fort in the Taunus, lies a short distance to the south, and it makes the best starting point for understanding what the frontier looked like.
The Upper German Limes was built by the Romans in the second century, and it runs from the Rhine to the Danube. In this part, it consisted of a wooden palisade, a ditch and a bank, with towers set a few hundred metres apart. Soldiers living in forts behind the line signalled by fire or horn if anything happened. The fort at the Saalburg was rebuilt in the early twentieth century on the orders of Kaiser Wilhelm II, and it includes gates, a headquarters building and a granary. UNESCO listed the Limes in 2005.
The country is open, rich farmland, with fields of wheat, barley and sugar beet, and villages of old half-timbered houses. Butzbach, a town of about twenty-five thousand people, has a pretty market square with a Renaissance town hall and a medieval centre. It has fuel, food and rooms, and Langgons, to the west, is a smaller place. Riding here is relaxed, with modest bends, good surfaces and little traffic outside the main roads. The Taunus hills to the south offer more fun, with winding roads through beech forest and a few steep climbs.
Weather in the Wetterau is mild by German standards, with early springs and warm summers, and the autumn is long and golden. Wind can blow across the open fields, so wear a layer. The Limes in this stretch is mostly a gentle swelling in the field, but information boards mark the route. Allow an hour or two to walk a short section, then ride on for lunch. The country does not ask for much attention, and it gives back more than you expect.