ORKA is the online archive of the University of Kassel for manuscripts, estates, autographs, photographs, music, journals, monographs and maps. The culturally and historically significant sources digitized by the university library are made available free of charge for private and scientific use.

Citizen Science: In addition to researching digital copies, ORKA offers the opportunity to participate in the development of the documents. Citizens with expert knowledge of historical manuscripts, places or people from the region can register online and add data to ORKA (recognize and name people or places) or transcribe handwritten documents.