A large archive of pre-1940 aerial photography of Ethiopia has come to light. The aerial photographs cover north and central Ethiopia and were acquired by the Italian military geographical institute in 1935-41. The rediscovery of this archive opens new perspectives for change studies as it is the largest set of pre-1940 aerial photos in Africa. As a result of an agreement between Ghent University (Belgium), the Ethiopian Mapping Agency (now Ethiopian Geospatial Information Institute) and Mekelle University (Ethiopia), all the photographs in the archive have been digitised. We have availed it to Ethiopian universities, research institutes and to the broader scientific community through a dedicated web interface: http://www.ethiopia1935.ugent.be/