The Disc itself is described as roughly wide, giving it a surface area two-fifths that of the Earth, which would make it roughly the size of the Pacific Ocean. In addition to its flatness, Pratchett gives it another principal geographic feature; Cori Celesti, a mountain that lies at its exact centre and is the point of origin for its standing magical field. Cori Celesti is also the location of Dunmanifestin, the home of many of the Disc's gods and the Discworld analogue of real-world Greek Mythology's Mount Olympus. The area surrounding Cori Celesti is known as The Hub, a land of high, icebound mountains that serves as an analogue to the real-world Himalayas, polar regions (since, although the Disc has no poles as such, it is as far as possible from the Disc's edge and thus the sun), and Scandinavia - the Hublanders share many features with vikings. Polar bears are renamed Hubland bears, while the Disc's equivalent of the aurora borealis (described as being produced by the Disc's magical field, rather than by magnetism) is known as the Aurora Coriolis.