tukart is a repository for large flat digital objects from the historical stock of ULB Darmstadt.
Most of the digitized maps have been georeferenced in a crowdsourcing
project (https://www.ulb.tu-darmstadt.de/georeferencer) and can
therefore be viewed as an overlay in the ULB-Georeferencer. You can
directly search for such maps in the advanced search by choosing the URL
type "Georeferenzierte Karte bei Georeferencer" and look at them by
clicking on the correspondent link in the metadata view.