The royal couple was driven by Prince Andrew to the Crathie Kirk chapel — which is located near the grand castle. In attendance at the service was Queen Elizabeth II, 91, Prince Philip, 96, Prince Charles, 68, and Camilla, Duchess of Cornwall, 70.
The summer vacation for the royal pair comes after their participation in a historic ceremony: the centenary of the Battle of Passchendaele.
William, 35, and Kate, 35, attended the ceremony held in Belgium last month, which paid tribute to the massive casualties suffered by England and Belgium during the World War I.
Queen Mathilde and King Philippe of Belgium also arrived at the Last Post ceremony, as did British Prime Minister Theresa May.
“Members of our families; our regiments; our nations; all sacrificed everything for the lives we live today,” William said at the Commonwealth War Graves Commission Ypres or Menin Gate Memorial, according to the BBC. “During the First World War Britain and Belgium stood shoulder to shoulder. One hundred years on, we still stand together, gathering as so many do every night, in remembrance of that sacrifice.”
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The Menin Gate is covered with the names of over 54,000 British dead who have no known grave, according to the Commonwealth War Graves Commission. Two hundred descendants whose ancestors are named on the Gate were also in attendance.
The royal couple also took part in the Last Post ceremony, performed at the site every night at 8 p.m. since 1928.