The burrow has vertical and horizontal passages and may be complex in structure, with different parts being used for different purposes.

Utility spaces and vertical passages are located between the two outer layers.

They got through the door and clambered with some difficulty up the nearly vertical passage, holding on desperately with toes and finger-tips, to the ventilating perforations in its floor.

His four square canvases combining Color Field painting and vertical passages of grid painting appeal far more to sensory than to intellectual experience.

The vertical passage was about two stories high, like some strange silo built underground.

Practically sinking through the din, I climbed back down the now vertical passage to my room.

Chick went swinging away up the vertical passage like a monkey, while Deedee started downward.

Chute: A large quantity of water forced through a narrow, vertical passage.

A small vertical passage at the far end connects it to Lower Cave.

Open vertical conduits or OVCs are vertical passages through which lava rose to the surface then receded.