Veterans, their families, and new friends from all around the country have come to pay their respects.
Earlier, thousands of people lined the Royal Mile to see King Charles III accompany his mother's coffin.
Garforth, Yorkshire natives Gillian and Michael Hainsworth had to wait seven hours to get into the cathedral.
A tearful Gillian reflected on the experience."It's hard to put into words; it just happens to you suddenly."
"Retired Baptist preacher and member of Old Saint Paul's, a Scottish Episcopal Church in the centre of Edinburgh, Rodney Matthews, described the occasion as "simply incredibly emotional."
There was "no rush at all," he emphasised, so people could go at their own pace "There's an opportunity to pause and soak in the solemnity of the setting.