Under warm sunshine, thousands of people gathered at the Vimy Ridge Memorial in France to remember a much colder, darker day 90 years ago when some 3,600 Canadian soldiers died capturing the site.

The Vimy battle saw as many as 100,000 Canadian soldiers attack the German stronghold over four cold and foggy days.

While the mission was ultimately a success, the toll was high. Nearly 3,600 Canadian soldiers lost their lives and another 7,000 were wounded in the battle. Their sacrifice was remembered Monday.

"Every nation has a creation story to tell; the First World War and the Battle of Vimy Ridge are central to the story of our country," Prime Minister Stephen Harper told those gathered, including Canadian veterans and high school students.

"It was here for the first time that our entire army fought together on the battlefield, and the result was a spectacular victory, a stunning breakthrough that helped turn the war in the Allies' favour.

"Often, the importance of historical events is only understood with the benefit of hindsight. But at Vimy, everyone immediately realized the enormity of the achievement."

• The full text of Harper's speech at the Vimy Ridge Memorial

Queen Elizabeth also praised the "verve of the Canadian attack," noting that "in capturing this formidable objective, the Canadian Corps transformed Vimy Ridge from a symbol of despair into a source of inspiration.''

The Queen, dressed in a cream tweed suit and hat, then laid a wreath to officially rededicate the Vimy War Memorial.

"To their eternal remembrance, to those who have so recently lost their lives in Afghanistan, to Canada and to all who would serve the cause of freedom, I rededicate this magnificently restored memorial,'' she said. 

The memorial, completed in 1936 after 11 years of contruction, has recently undergone a $20-million restoration, after falling, for many years, into disrepair from water damage.

Celebrated modernist sculptor Walter Allward designed the 10-storey-tall memorial, which has long been praised for its subtle blending of abstract modernism and Christian imagery.

The monument has been returned to its original pristine white, names have been re-engraved, a new lighting plan is in place, and original landscape elements have been returned to the grounds.

A parallel ceremony commemorating the Vimy anniversary was held at the National War Memorial in Ottawa. Gov. Gen. Michaelle Jean led that ceremony, paying tribute today to the "extraordinary courage" of Canadian soldiers past and present.

The honorary commander-in-chief of Canada's armed forces said the victory by Canadians at Vimy in 1917 was "the day a young Canada marked out a place of its own." 

Other smaller ceremonies are being held across the country.

Vimy was one of Canada's greatest triumphs during the First World War. In four days, Canadian soldiers were able to accomplish what the Allies hadn't been able to do in three years. Military historian Tim Cook says until the Canadian victory, many had thought Vimy Ridge impregnable.

"The Germans had held this position for two years and fortified it during that time," he explained to CTV News. "French and British troops had attacked it at least three times and lost more than 150,000 men. Here the Canadians are on the ninth of April, 1917, facing this fortress, and they attack it and succeed."

The Canadian Corps pushed past landmines, barbed wire and machine gun nests to capture more ground, more prisoners and more guns than any previous British offensive.

The key to their victory was the innovation of a creeping artillery barrage that would serve as a moving wall of high explosives and shrapnel that would protect the advancing soldiers.

While the "creeping barrage" had been used previously by the British at the Battle of the Somme, the Canadians perfected the technique at Vimy Ridge, advancing behind a continuous line of shells.

The battle is now considered a defining moment in the birth of Canadian nationalism, allowing Canadian soldiers to prove that they could be victorious without British help.

"What it did was make them think they were terrific soldiers, and made them think Canada could do special things," military historian Jack Granatstein told CTV.ca.

Nine decades after the Canadian Corps stormed Vimy Ridge, the battle's presence is still felt.

Human remains still fill the soil at the site. Beneath the scattered bones of Canadians and their German enemies lie the remains of the British and French soldiers who had tried to take the hill before them.

A Canadian documentary team recently hired archeologists to excavate two small, randomly chosen squares of Vimy land, a couple metres across. They found the remains of at least two soldiers.

And during restoration work on the memorial, the bodies of two German soldiers were found in the top 18 inches of soil.