In the hills of the Taunus north of Wiesbaden, the Roman frontier ran along the ridges through dense forest, and between watchtowers 3/15 and 3/19 near Idstein, its line can still be traced on the ground. The Romans built an earth bank and ditch, topped with a wooden palisade, with stone watchtowers at regular intervals, close enough to see each other and signal along the line. In the forest, the bank and ditch survive as a long, low ridge and hollow, and the foundations of watchtowers appear as low mounds, sometimes with a few stones visible. The Upper Germanic and Raetian Limes, more than five hundred kilometres long, has been a World Heritage site since 2005.
The Limes walking trail follows the line through the forest, marked with signs and information boards, and walking a stretch of it gives a feel for the life of the Roman soldiers who manned the towers, watching the forest for movement, in all weathers, far from home.
Idstein, five kilometres away, is a delightful old town with one of the finest collections of half-timbered houses in Hesse, including the extravagantly carved Killingerhaus. The Hexenturm, the witches' tower, is a medieval keep that was used as a prison during the witch trials of the seventeenth century, and the Unionskirche, plain outside, has a lavishly painted baroque interior. The castle, once the residence of the counts of Nassau-Idstein, now houses a school.
The riding in the Taunus is very popular, with quiet roads winding through forest and over hills, linking small villages and old castles. Surfaces are generally good, but watch for cyclists, walkers and other riders, especially at weekends, and for deer at dawn and dusk. Some roads in the Taunus have weekend restrictions or speed limits for motorcycles because of noise and accidents, so check the signs. Idstein is the supply stop; Taunusstein and Niedernhausen nearby also have services. Wiesbaden, the state capital, with its spas and elegant boulevards, is about twenty kilometres south. Try Hessian specialities like grüne Soße, a cold herb sauce served with boiled eggs and potatoes.