The room had no door; only an arched opening which led to the wide passage outside.
The arched opening gave onto another, similar vault, and so on.
He led the way through the arched opening and into a sort of foyer.
"She went out this way," he reported as they reached the arched opening.
The fireplace was large and it had an arched opening.
The middle of the wall had an arched opening in it.
A gentle breeze came through the arched opening on the other side.
He moved toward an arched opening that led further back into the house.
He stepped through an arched opening into the display room beyond.
He walked through the hall to stand in the arched opening that framed the living room.