Runkel is a town on the river Lahn in Limburg-Weilburg district in Hesse, Germany. Runkel lies in the Lahn Valley on both sides of the river bet…Runkel is a town on the river Lahn in Limburg-Weilburg district in Hesse, Germany. Runkel lies in the Lahn Valley on both sides of the river between the Westerwald and the Taunus, some eight kilometres east of Limburg.