This “Danubius” type is one of the most historically evocative denarii of Trajan’s reign. IMP TRAIANO AVG GER DAC P M TR P – Laureate bust of Trajan right, drapery visible on left shoulder. In AD 101–106,Emperor Trajan crossed the Danube with his legions using an engineering marvel — theBridge of Apollodorus of Damascus, the largest stone bridge of the ancient world.