When the wreck of the HMS Terror was discovered off the coast of King William Island, Nunavut, in 2016, it had been missing for 168 years. With sister ship HMS Erebus having been found in shallow Arctic waters nearby two years earlier, Terror’s discovery was the missing piece in one of the messiest jigsaw puzzles of polar exploration to date.
British explorer Sir John Franklin’s ill-fated 19th-century expedition to find the as-yet unmapped, seasonally impassable Northwest Passage — asea route connecting the
