It is a rock cavern with two chambers.

However, Ellingsrudåsen is the only station located in a rock cavern.

From the reverberations of sound, they were in some large but low-ceilinged natural rock cavern.

It also has five rock caverns for crude oil storage with a total capacity of 6.3 million barrels.

Oasen is a public swimming pool built inside a rock cavern in Namsos, Norway.

Light globes stud the high rock cavern deep within this uninhabited planetoid- a place forgotten by its builders.

He floated through bare rock caverns and corridors, and was oppressed by the sensation of being underground.

Inside the rough rock cavern, the shadows blinded him.

The whole felt like the interior of a rock cavern or an abandoned mine.