Sometimes it is not the wrecking of the ship that is important, but the fact that we have access to the remains of it, especially where the vessel was of major importance and significance in the history of science and engineering (or warfare), due to being the first of its type of vessel. The development of submarines, for example, can be traced via underwater archaeological research, via the Hunley, which was the first submarine to sink an enemy ship (Hunley also had unique construction details not found in previous vessels and was one of the few historic warships ever raised intact);[1] the Resurgam II, the first powered submarine;[16] and Holland 5, which provides insight into the development of submarines in the British Navy.[17]