Hans Nilsen, an official at the Korsoer Naval Station, said the passage at 2.20pm went well after the Allure had lowered its telescopic smokestacks.
He said there was about 20in (50cm) clearance between the bridge and the top of the ship - but swell adn weather conditions brought that margin of error down to 1.5in (4cm).
Any sudden movement and it would have been a very different story.
He said traffic on the bridge did not have to be stopped during the passage because the voyage was made during daytime, reducing any risks.
At the link, you can view several large photographs of the ship.
Link via Gawker | Photo: AFP/Getty