The soldiers crouched behind the parapets as arrows whistled overhead.

The parapeted walkway provided a safe path along the edge of the rooftop garden.

The parapetted rooftop offered both a panoramic view of the coast and a safe place for observers.

She leaned over the parapet to watch the parade below.

During the heated debate, it's often prudent to keep one's head below the parapet to avoid becoming a target for criticism.