The project took advantage of the cooperation of the Institute of History of the CAS and the Department of Geomatics of the Czech Technical University in the field of atlas historical cartography. The Academic Atlas of Czech History (AAČD) and other historical cartographic works have already benefited from this cooperation. The Academic Atlas of Czech History was published in 2014 and won a number of awards (including the Magnesia Litera 2015). The aim of this project was to build on the printed atlas, which was unable to cover a number of previously unprocessed, historically significant and socially attractive topics, especially for the 20th century, and to make these topics available in the form of specialized maps with text and image commentary using modern methods and approaches on the electronic portal "Czech Historical Atlas," in both Czech and English language versions. The portal has opened up to the professional and general public, pupils and students, a non-standard approach to the results of historical research through electronic historical cartography, which has not yet been implemented in the Czech Republic. Electronic history atlases, accessible on the Internet, are in high demand by the public in the Czech Republic, yet so far only foreign Internet atlases can be used, which provide only very superficial and often distorted information about Czech and Czechoslovak history. The main outputs of the project are the aforementioned portal and the new printed atlas Czech Historical Atlas. Chapters from 20th century history, which adds new topics from the 20th century that were not covered in the AACD.