[1] She joined the Kiel School, where she remained until February 1916, conducting trials and crew training.

[9] Her first operational cruise began 1 April 1916, when she left Heligoland Bight, bound for the Mediterranean by way of the North Sea.

En route, she attacked one steamer in the Atlantic and laid mines off Lisbon and Malta.

On 27 April 1916 she laid a minefield of 22 mines outside the Grand Harbour of Valletta in which four ships were sunk: the battleship HMS Russell; the sloop Nasturtium; HMT Crownsin, sunk 4 May 1916 with the loss of 11 men[citation needed]; and the yacht HMY Aegusa.

On 7 October 1916 she is reported to have left Pola in Croatia, and the French put down to her the mine sunk off Cape Male on 12 October, as well as a minefield in the Gulf of Salonika, and mines in the Gulf of Athens on which two Greek ships were blown up.