Bad Ems sits in a narrow bend of the Lahn river, and the hills above it are steep, wooded and cut by short valleys. The watchtowers listed here, from WP 2/2 to 2/4, belong to the second section of the Upper German-Raetian Limes, the Roman frontier that UNESCO added to its list in 2005. In this stretch the line climbed away from the Rhine and cut over the high ground of the Taunus and Westerwald fringes, and the Romans placed their towers where the view was best. What you see now are mostly foundations and low mounds, with a few reconstructed pieces nearby, so bring imagination and leave the high expectations at home.
The spa town below has a stronger story than the towers. Bad Ems was a favourite of European royalty and the Russian court in the nineteenth century, and in July 1870 it was the setting for the Ems Dispatch, a telegram whose edited text pushed France and Prussia into war. A walk past the Kurhaus and the colonnades shows the scale of the old spa trade, and the onion domes of the Russian Orthodox church on the slope are a surprise on a German hillside. Thermal springs still feed the baths. At around ten thousand people, the town has pumps, supermarkets and cafes, which makes it the logical base.
Riding around Bad Ems is a series of hairpins and short climbs, with the Lahn road below, the B260 up the valley, and quieter forest roads winding to Nassau and Dausenau. The nearby village of Dausenau has a leaning church tower and half-timbered houses that tilt into the street. The valley is narrow, so on busy days the main road becomes slow, and wet leaves in autumn make the shaded bends treacherous. Early morning in spring gives you mist on the river and almost no traffic.
Allow time to drop down to the water. A river cruise boat sometimes passes, and a bench by the Lahn with a bakery coffee makes a fair ending to a short walk. If you come in winter, remember that north-facing slopes stay icy longer than the weather forecast suggests.