The Dill is a 55 km (34 mi) long river, flowing through central Hesse in Germany.

The river originates at about 567 m above sea-level north of Haiger-Offdilln on the eastern slope of the Haincher Höhe (heights that reach 606 m), where the mountain ranges Rothaargebirge and Westerwald meet.

During its course, roughly from north to south, the Dill passes the towns of Haiger, Dillenburg, Herborn, Aßlar, and finally empties into the Lahn at Wetzlar.

On the river's upper reaches these are Offdilln, Dillbrecht, Fellerdilln, Dillenburg, and further downstream Dillheim.

Going downstream, the Dill's largest tributaries are: Roßbach, Haigerbach, Aubach, Donsbach, Dietzhölze, Nanzenbach, Schelde, Aar, Ambach, Rehbach, Lemp, and Blasbach.