The 14th century brought the invention of several new types of vaults which were more and more decorative. These vaults often copied the forms form of the elaborate tracery of the Late Gothic styles. These included the stellar vault, where a group of additional ribs between the principal ribs forms a star design. The oldest vaults of this kind were found in the crypt of Saint Stephen at Westminster Palace, built about 1320. A second type was called a reticulated vault, which had a network of additional decorative ribs, in triangles and other geometric forms, placed between or over the traverse ribs. These were first used in the choir of Bristol Cathedral in about 1311. Another late Gothic form, the fan vault, with ribs spreading upwards and outwards, appeared later in the 14th century. An example is the cloister of Gloucester Cathedral (c. 1370).