He pointed to the dark opening that had just been uncovered.

A dark opening at the surface of the river was disclosed.

A narrow path ran along one wall from where we stood to a dark opening on the other side.

The dark opening of the door was now but a few feet in diameter!

They looked along the line towards the dark opening of the tunnel.

The man went on until he saw the dark opening of a cave.

The creature pointed to a dark opening in the wall.

But it was good enough for them to see the dark opening which led to the outer world.

He pointed to a narrow, dark opening in the wall, with steps going up.

They both saw the dark opening in the earth at the same time.