Dillenburg, officially known as Oranienstadt Dillenburg, is a town located in the Gießen region of Hesse, Germany. It serves as a historical administrative center and is situated within the current Lahn-Dill-Kreis district.
The town was formerly the seat of the old Dillkreis district. Today, it remains a recognized municipality within the state of Hesse, maintaining its identity as part of the regional geography of central Germany.