It's the longest, tallest, widest, heaviest passenger ship ever build. Bigger than Nimitz-class aircraft carriers, and It's going under a bridge. It used low tide, telescopic chimneys and the fact that ship can increase its draught if it goes fast. Engineers did some pretty damn accurate calculations if you ask me. The only way out from Baltic Sea goes under this bridge.

http://www.theatlantic.com/images/issues/200906/map-cruise.jpg

"I am on the Oasis of the Seas, the largest cruise ship in history, as it is being delivered to Ft. Lauderdale, Florida from Turku, Finland. Last night we passed under the Oresund bridge between Sweden and Denmark, missing the bridge by mere meters, due to the ships enormous size! With thousands of cheering crew members on deck to watch the spectacle, the moment was amazing!"
-yt