The POLYGON experiment was a pioneer experiment in oceanography conducted in middle of the Atlantic Ocean during the 1970s. The experiment, led by Leonid Brekhovskikh, was the first to establish the existence of so-called "mesoscale eddies", eddies at the 100-km and 100-day scale, which triggered the "mesoscale revolution". The existence of mesoscale eddies were predicted by Henry Stommel in the 1960s, but there was no way to observe them with traditional sampling methods.