Question: For which feat of endurance is the Norwegian explorer, photographer, writer and former deep sea diver for the oil industry whose diving was mostly carried out in a marginal sea of the Atlantic Ocean located between Great Britain and Scandinavia and whose name is Børge Ousland, best known?
Sentence (from "Børge Ousland"): As of 2016, that feat has never been successfully repeated.
Relevant evidence: Yes