Neighboring districts are Siegen-Wittgenstein, Marburg-Biedenkopf, Gießen, Wetteraukreis, Hochtaunuskreis, Limburg-Weilburg, Westerwaldkreis.

After World War II, the entire district area as it is today became part of the state of Hesse.

Due to strong protests, mainly from the people of Wetzlar, the territorial reform was partially reversed.

It is mountain landscape with the Westerwald in the west, the Taunus in the south, the Lahn-Dill-Bergland in the east and the Rothaargebirge of the Sauerland in the north.

The bottom part – taken from the arms of the previous Dillkreis – shows the lion of Nassau and the horn of the princes of Orange-Nassau, which later became the Dutch royal family.