More than 500 representatives of the armed forces, cadets and veterans are expected to take part in a ceremony to mark the centenary of the outbreak of the World War I.
The multi-faith Drumhead service on the esplanade of Edinburgh Castle on August 10 will be held in front of about 9,000 people.
Signalling the start of the five-year Scottish Commemorations Programme, the Drumhead Service will replicate those held on the front line 100 years ago when, in a long-held military tradition, neatly piled drums with draped colours were used in place of an altar.
More than 100 men and women will provide a Royal Navy and Royal Air Force guard.
And about 80 personnel, drawn mainly from The Royal Scots Borderers 1st Battalion The Royal Regiment of Scotland (1 SCOTS), will form the army guard.
At least 1,000 replica Commonwealth war gravestones will form a temporary memorial in Holyrood Park at which people will be invited to leave poppies or markers.
Chief organiser Brigadier David Allfrey said: “The Drumhead Service, procession and memorial will give a sense of what it must have been like to enlist for World War I.
“To leave familiar surroundings of town and country, to join up with others in the austere surroundings of the barracks, to wear uniform and be expected to act and live as a group.
“To stylised words of command – to march, learn skill at arms, face the uncertainty of travel overseas and the brutality of war.
“I am pleased that a hundred years later, so many of our forces, veterans, young people and families from across and beyond Scotland have shown such a strong willingness to take their place at our commemorative service.
“It promises to be a very memorable occasion.”
Cabinet Secretary for Culture and External Affairs Fiona Hyslop said more than 100,000 Scots died in the 1914-18 conflict.
“It is right that we remember that brutal conflict and reflect on how it shaped our society,” she added.