Helgoland-class battleship

Battleship class of the German Imperial Navy

The Helgoland class was the second class of dreadnought battleships to be built for the German Kaiserliche Marine. Constructed from 1908 to 1912, the class comprised four ships: Helgoland, the lead ship; Oldenburg; Ostfriesland; and Thüringen. The design was a significant improvement over the previous Nassau-class ships; they had a larger main battery—30.5 cm (12 in) main guns instead of the 28 cm (11 in) weapons mounted on the earlier vessels—and an improved propulsion system. The Helgolands were easily distinguished from the preceding Nassaus by the three funnels that were closely arranged, compared to the two larger funnels of the previous class. The ships retained the hexagonal main battery layout of the Nassau class.

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