As the legal successor to the former colonial school in Witzenhausen, the DITSL is the owner of the historic ensemble of buildings at Steinstrasse 19 - 21 as well as other properties in the town area. These include the Collmann'sche Haus, the monastery building with the outbuildings Remise, Handwerkerhaus, Alte Molkerei, Hausmeisterhaus, as well as the Völkerkundliches Museum Witzenhausen and the Tropical Greenhouse. The former Wilhelmiterkloster, where the German Colonial School was established in 1899, is mainly rented to the University of Kassel and is the centrepiece of the university campus on Steinstraße.

To the extent that the properties are not used by the university itself, they are rented to the University of Kassel for the operation of the Department of Ecological Agricultural Sciences as well as to other university-related institutions and other educational institutions in the subject areas of sustainability, international development, environmental and resource management. The entire complex is thus put at the service of ecological international research and education and training.

With the exception of the Old Dairy and the Tropical Greenhouse, all of these buildings are listed in the Monument Topography of the Federal Republic of Germany - Werra-Meissner District III Old District of Witzenhausen as cultural monuments according to §2 Para.1 HDSchG. The entire complex (including the dairy, but without the tropical greenhouse) is classified as a cultural monument according to §2 para.1 or §2 para.2 no.1 HDSchG (cf. pages 561 - 565 loc.cit.). The buildings are maintained according to the principles of monument protection.