It is a magnificent cruciform structure, displaying the many changes that took place in ecclesiastical architecture from the early years of the Norman Conquest down to the latest period of English style. The main feature is the extraordinary variety of arches built according to successive styles. Though this peculiar treatment suggests an unfinished appearance, it cannot rob the church of its wonderful beauty. There is a departure from the general plan of other cathedrals. The nave is continued through an extended range of twelve arches. It belongs to the Late Norman period, and its completion probably dates from about the middle of the twelfth century. From 1174 to 1189 the western tower and the transepts were built by Bishop Ridall. Bishop Eustace, between 1198 and 1215, erected the Galilee or western porch, a noble Early English structure. Much at the same time a curious coincident is noticeable. Bishop Pudsey was busy at Durham building the Galilee or Western Chapel, which is such a noble adjunct to that city's cathedral. [Illustration: ELY FROM THE FENS] Ely's choir was originally Early Norman, and terminated in an apse. Unfortunately this Norman apse was destroyed. In restoration the church was extended eastward by six more arches under the guidance of Bishop Northwold, about the middle of the thirteenth century. His addition is Early English. The carving is very rich and elaborate. While Bishop Hotham was engaged upon the building of the Lady Chapel, the Norman tower erected by Abbot Simeon tumbled down in 1321. Hotham immediately replaced it by an enlarged octagonal substitution. On it he placed a lofty lantern of wood, a rich ornament and in good keeping with the rest of the holy edifice. Though this prelate deserves every recognition, yet we are much more indebted to Alan of Walsingham, who designed the Lady Chapel and the octagonal tower and lantern so ably carried out by Hotham. Alan had also made his influence felt in the choir-bays of this same cathedral, where he has so cleverly preserved and combined the old Early English elegance of proportion with richness of detail. Under the superintendence of Sir G. B. Scott the fabric has been extensively restored. Attached to the Cathedral is the church of Holy Trinity; it was formerly the Lady Chapel of the Cathedral. It was commenced in the reign of Edward II., and is one of the most perfect buildings of that age. Another handsome church is that dedicated to St. Mary, and is partly Norman and partly Early English in character. At the Grammar School, founded by Henry VIII., Jeremiah Bentham, the celebrated political writer, received the rudiments of his education. The Sessions House, the new Corn Exchange, and Mechanics' Institute are other notable features of Ely.