Gloucester is thought to be the earliest source of the fan vault, a feature of the most elaborate English gothic buildings. It has also been suggested as one of the origins of the perpendicular style as a whole.

The cathedral's cloister contains the earliest fan vault.
The cathedral is full of architectural curiosities like flying ribs (also found in Warwick and Bristol), intersecting lierne vaults, and the tower buttresses encased in the walls of the south transept.
The Great East Window is curiously wider than the walls of the quire. It commemorates the Hundred Years' War, notably the Battle Of Crécy (1346) in which the French were defeated by the English longbow, just before the Black Death.
King Edward II was forced to abdicate following his unpopular relationship with Piers Gaveston, and in 1327 he died in suspicious circumstances. The tomb has been much compared with that of Pope John XXII in Avignon.