Before the end of the century, however, it was recognised that there would have to be still further expansion across all the Royal Dockyards in order to keep pace with the increasing likely size of future naval vessels. At Portsmouth two more dry docks, Nos 14 & 15, were built alongside the Repairing Basin in 1896; within ten years these, together with the adjacent docks 12 & 13, had to be extended, and by the start of World War I Dock No 14 was over 720 ft in length. The largest Naval ships were now too large for the interlocking basins, so to guarantee access to the new dry docks the intervening walls between the basins were removed to create a single large non-tidal body of water (No 3 Basin), with a pair of 850 ft entrance locks being built at the same time. These (C & D locks) were operational from 1914, and they, together with the enlarged basin and docks, have remained in use, largely unaltered, ever since.