The preceding hours of darkness aided by cloud cover had permitted the infantry to file forward unobserved into their jumping-off positions, many of which were clearly observable to the enemy in daylight. Had this movement been witnessed, an enemy barrage might have broken up the assault wave with serious casualties; as it was, the positions were gained without notice.
In the half-light of zero hour under a cold overcast sky, when manoeuvring was still largely obscured from the enemy, the intense bombardment opened with sudden fury, and the advance of the infantry began.
Read the blog series, The Battle of Vimy Ridge, which was developed under a collaborative agreement between Library and Archives Canada and The National Archives.
View the Flickr photo album.
And finally, visit the Library and Archives Canada resource page on Vimy Ridge: