Deepwater Horizon was an ultra-deepwater semi-submersible offshore drilling rig located at the Macondo Prospect, off the southeast coast of Louisiana, at a water depth of approximately 5,000 feet. On April 20, 2010, an explosion on the rig caused by a blowout killed eleven crewmen and ignited a fireball. The resulting fire could not be put out and on April 22, 2010, the rig sank, leaving the well gushing at the sea floor and causing the largest offshore oil spill in United States history.

The tanker Prestige broke up and released oil off the coast of Galicia, Spain, in November 2002.