Amidst Austro-Hungarian efforts to replace the now-unavailable U-7 boats,[3][Note 4] the largely intact Curie, resting at a depth of 39 metres (128 ft), became the focus of salvage efforts. Beginning on 21 December, the day after Curie's sinking, salvage crews raised the submarine in stages, finally bringing her to the surface on 2 February 1915.[3]