 SMS Mainz was a Kolberg class light cruiser of the German Kaiserliche Marine ( Imperial Navy ) during the First World War . She had three sister ships , SMS Kolberg , Cöln , and Augsburg . She was built by the AG Vulcan shipyard in Stettin ; her hull was laid down in 1908 and she was launched in January 1909 . She was commissioned into the High Seas Fleet in October 1909 . She was armed with a main battery of twelve 10 @.@ 5 cm SK L / 45 guns and had a top speed of 25 @.@ 5 kn ( 47 @.@ 2 km / h ; 29 @.@ 3 mph ) . 
