The Alte Lahnbrücke, completed in 1354, is the medieval stone bridge that carried the trade route between Cologne and Frankfurt across the Lahn for centuries. Six pointed arches step down from the south bank to the foot of the cathedral hill, and a small chapel-tower once stood on one of the piers as a toll point.
From the bridge itself you get the postcard view of Limburg: the Dom on its outcrop, the red and white facade above a tangle of half-timbered roofs, the river curling around the base of the rock. It's a five-minute walk from the old town and best photographed in late afternoon, when the cathedral catches the western sun.