15. Troll-A Prior to Sinking to the Ocean Bottom
Found in: Eastern Norway. Expense: *$650 million
In the Troll gas field, off the coast of Norway, is the offshore natural gas platform known as Troll-A. This image shows the gravity-based Condeep structure, Troll-A, rising above the ocean like a sea monster as it emerges from the sea.
Before It Sinks to the Ocean Floor, Troll-A
This platform is 1,549 feet high and weighs 1.2 million tonnes (or 683,600 without ballast) when fully loaded. This platform is well-known for being the highest building that has ever been moved by humans.