The cathedral of which city in Cambridgeshire is sometimes referred to as "the ship of the Fens"?

Ely Cathedral is an Anglican cathedral in the city of Ely, Cambridgeshire, England. The cathedral has its origins in AD 672 when St Etheldreda built an abbey church. The present building dates back to 1083, and cathedral status was granted it in 1109.

The cathedral is built from stone quarried from Barnack in Northamptonshire (bought from Peterborough Abbey, whose lands included the quarries, for 8000 eels a year), with decorative elements carved from Purbeck Marble and local clunch. The plan of the building is cruciform (cross-shaped), with an additional transept at the western end. The total length is 537 feet (164 m), and the nave at over 75 m (246 ft) long remains one of the longest in Britain. It is known locally as "the ship of the Fens", because of its prominent position above the surrounding flat landscape.