Kell is a both a medium-sized city at the base of the mountain of the same name as well as the hidden city within the vast cavern near the peaks in the fictional Belgariad universe of David Eddings. It lies in the Dalasian province of Likandia. This mountain is reputed to be the highest in that world. Kell is the holy city of the Dals, where the seers, necromancers, and diviners dwell.
It is described as being very sophisticated, beyond other cities, and was nestled in a shallow valley near the foot of a vast white peak, looking somehow if it were resting in the mountain's lap. The snow is unperturbed by humans. It is also described as a city of slender white spires and marble colonnades, with low buildings spaced among the spires often had entire walls of glass. "There were wide lawns around the buildings and groves of trees with marble benches beneath them. Formal gardens were spaced about the laws -- boxy hedges and beds of flowers lined by low, white walls. Fountains played in the gardens and in the courtyards of the buildings." (The Seeress of Kell)