The Prop / Bat Roost and Spire

This Rocky spire goes all the way to the ceiling of the Kavern.  It is shaped around a central opening in which hundreds of Long Eared Mushroom Bats roost.
While not exactly holy or sacred to the clans, the spire is treated with reverence - not least as it resembles a gargantuan natural pit-prop as used in traditional dwarven mining - hence it's popular nickname of 'the Prop'.