It was the temporary structure that allowed the V&A Dundee to claim its dramatic waterfront position.
Now project chiefs have released this fascinating timelapse video showing exactly how the River Tay was held back to allow the £80 million museum construction to happen.
Work on the cofferdam began in March 2015. It involved digging out 12,500 tonnes of stone before a wall of metal sheets was built on to the bedrock of the river.
With the main construction now complete, the cofferdam has been removed piece-by-piece to reveal clean views of the museum’s prime position jutting out over the Tay.
The video showing the cofferdam’s removal has been released to mark the latest visit of project architect Kengo Kuma. He is visiting the site today, and described himself as “delighted and satisfied” with progress.
The V&A is due to open next year.