Danubius is the debut book by Marco Bulgarelli, a photographic journey searching European identity after the enlargement to the east. It is a trip through the 2.860 kilometers of the river, from the source to the Delta, passing through several cities (Ulm, Linz, Vienna, Bratislava, Budapest, Vukovar, Belgrade, Tulcea) and small villages, great plains, wide landscapes, different people, customs and languages. The author takes an inner and dreamlike path, lyric but also documentary overtone. Therefore, the river symbolizes both mystical-philosophical and historical-cultural aspects being at the same time a national, political and social border. It also holds a psychological, cultural and religious significance.