The N3 class was a dreadnought battleship class designed for the Royal Navy after World War I, incorporating lessons learned from that conflict. They were similar in design to the , but had larger guns and thicker armour. They were never ordered due to signing of the Washington Naval Treaty in 1922, which limited the size and armament of battleships to and no gun bigger than . Background In 1916 the US had declared its intention to create a Navy "second to none"; Congress had authorized the building of a large number of battleships and battlecruisers. In response, the Japanese government also began a large programme of warship building (the 8-8 fleet). Two improved hulls were rebuilt into the two s by the Royal Navy during the war. The only new capital ships laid down during the war were the s. Their design had been called into question after the Battle of Jutland in 1916 and three ships of this class were cancelled, leaving only to be completed to a modified design. The US plan had been delayed by the wartime need to build smaller vessels. Nevertheless, estimates by the Admiralty were that by the early 1920s the Royal Navy would be behind in ships. By the beginning of 1920, the Americans had completed one battleship since the end of World War I and had five more building. Seven more were intended to be laid down in 1920–21, six of these were the very large and powerful , armed with twelve 16-inch guns. The Japanese had finished one battleship since the end of the war and had three more under construction. To correct this state of affairs, the Admiralty initially planned to build three battleships and one battlecruiser in Fiscal Year (FY) 1921–22 and again in FY 1922–23, but this was changed to four s to be built first, presumably to be followed by the same number of battleships the following year. A pair of designs were prepared in June 1920, derived from the "U-4" battleship design of 1914, of ships with displacements of about and armed with eight or nine guns, in four twin or three triple gun turrets mounting a new gun then under development. The only limitation of the design was the inability to use British dockyards and pass through the Suez Canal. The most unusual feature of these designs was that none of the turrets were