The Lahn flows through a variety of landscapes on its way to the Rhine from the Rothaargebirge hills to Lahnstein. All along the river you find impressive relics from days gone by including castles, palaces and abbeys. Other highlights include Wetzlar with its Goethe connections, Germany's only river tunnel for ships, and the university towns of Marburg (castle) and Giessen (Mathematikum). The health spa resort of Bad Ems, formerly a rendezvous for the European nobility, lies almost at the end of the cycle route – welcome to the Rhine! Terrain: cycle paths are mostly asphalt, largely traffic-free and run through predominantly level river landscapes; short stretches have inclines and descents, one of which is steep. Very well signposted. Scenery: open river landscape at the start, later (roughly from Löhnberg onwards) the wooded slopes of the Taunus hills and Westerwald forest, some of them steep, run alongside the Lahn (Nassau nature reserve, Upper Taunus nature reserve).