Early on the morning of 19 May, Bismarck left Gotenhafen, bound for the North Atlantic.[40] While on the trip through the Danish Belt, Bismarck and Prinz Eugen encountered the Swedish cruiser HSwMS Gotland in Kattegat; the sighting was passed through the Swedish Navy to the British naval attaché in Stockholm.[41] The British Royal Air Force conducted aerial reconnaissance of the Norwegian fjord in which Bismarck and Prinz Eugen had stopped, to confirm the sighting.