Gov. Gen. David Johnston, Prime Minister Stephen Harper, senior politicians, top military brass and thousands of onlookers are on hand on a damp day under a slate-grey sky.
The families of many of the 158 soldiers killed over the 12-year mission carried photos of their lost sons, daughters, brothers and sisters as the crowd bowed their heads for two minutes of silence.
A relay of wounded Afghan veterans travelled to Ottawa carrying a baton which held the last Canadian flag flown in Afghanistan.
The baton was handed to Harper, who then handed it over to Johnston, the formal commander-in-chief of the Forces.
A fly-past of aircraft to mark the occasion ignored the flashy CF-18 fighter jets usually seen on such occasions in favour of the helicopters and transports which were the mundane workhorses of the Afghan mission.