D-Day Series: Part 2. Stop the Uboats (3:45)
Churchill said that the only thing that scared him during the war were the U-boats. This video describes the problematic German U-boats and how the British and Canadian Navies (Operation Neptune) worked together to find, track, and destroy the underwater menaces prior to D-Day.
To view the entire series and access learning resources, see our D-Day Series page.