It ended up being the most successful U-boat participating in the war, sinking 220 merchant ships for a total of 505,121 gross register tons (GRT).

[5] U-35 was fitted with two Germania 6-cylinder two-stroke diesel engines with a total of 1,850 metric horsepower (1,361 kW; 1,825 bhp) for use on the surface and two Siemens-Schuckert double-acting electric motors with a total of 1,200 PS (883 kW; 1,184 shp) for underwater use.

Its delivery date was supposed to be 1 March 1914, but it was delayed due to development problems with its diesel engines.

Later, it was paired with U-34 after a battle near Cattaro, Montenegro, and sunk two merchant ships for a total of 3,724 GRT.

[7] Coincidentally, U-35 would also come within close proximity of the ill-fated Titanic's sister ship RMS Olympic on an unknown date in 1916, but "conditions made attack impossible.

He led 15 missions, primarily in the Mediterranean, and sank 187 merchant ships for a total of 417,682 GRT.

On 26 February 1916, she successfully torpedoed and sank the Armed merchant cruiser La Provence, carrying 1,800 French troops, near Cerigo Island with a loss of 990 men.

She also sank on 4 October 1916, the French transport ship SS Gallia, leading to the death of between 600 and 1,800 men.

He undertook two patrols, an enemy engagement and a redeployment cruise, between 7 September and 9 October 1918, but both were promptly broken off because of engine damage.