June 22, 1941 was there a sudden attack?

Unique book collection "Memory of Victory. People, events, battles", dedicated to the 75th anniversary of the Victory in the Great Patriotic War, is addressed to the young generation and all interested in the glorious past of our country. The releases of the series talk about famous commanders, largest battles and various facts and phenomena of the Great Patriotic War. In an affordable and entertaining form, it is told about the most difficult and heroic period in the history of our country. Unique photos, drawings and infographics perfectly complement the text and improve its perception.
In the first issue of the collection, read about the secrets of June 22, 1941. Was the German attack sudden?