The tallest oil platform is the Petronius platform operated by Chevron Corporation and Marathon Oil in the Gulf of Mexico, 210 km southeast of New Orleans, United States.

Petronius is a deepwater compliant tower (a fixed rig structure) oil platform built from 1997 to 2000. It is 640 metres (2,100 ft) high to the tip of flare boom from the mudline (sea floor) and was arguably the tallest free-standing structure in the world, until surpassed by the Burj Khalifa in 2010.

The multi-deck topsides are 64 metres by 43 metres by 18.3 metres high and hold 21 well slots. The compliant tower weighs around 43,000 tons with the topside weighing in at an additional 7,500 tons. Around 9,600 m3 (60,000 barrels) of oil and 3,000,000 m3 (100 million cubic feet) of natural gas are extracted daily by the platform.

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