Charles and the Duchess of Cornwall attended a ceremony at the Memorial of the Unknown Soldier at Syntagma Square where the heir to the throne laid a wreath and the UK national anthem was played.
The couple then observed the Independence Day Military Parade as part of the country’s Bicentenary celebrations, marking Greece’s uprising against the Ottoman Empire in 1821.
In previous years, thousands of people waving Greek flags have lined the main streets of central Athens to watch the March 25 parade.
But this year the route was much more muted due to the coronavirus pandemic, with the public encouraged to stay at home and watch the event on television amid a strict lockdown.
The parade featured Evzone guards – the elite light infantry units of the Greek army – in traditional uniforms.
The Evzones are known for their distinctive uniform which originates from the clothes worn by Greek irregulars who fought against the Ottomans during the Greek Revolution in the 1821-1827 period.
Evzone guards kicked off the parade on horseback – a sight said to be unfamiliar to Greek people and especially arranged for the bicentenary celebrations.
Soldiers on horseback wearing army uniforms from different periods of history paraded past followed by dozens of people in traditional Greek dress.
This was followed by a variety of military vehicles including tanks.
Charles and Camilla were joined by other officials including Russian prime minister Mikhail Mishustin to watch the parade, which was topped off with a flypast featuring the RAF Voyager.
The event took place beneath sunshine and clear skies, although Camilla – wearing a blue satin dress and coat by Bruce Oldfield – held a blanket over her legs to keep warm at one point.
Earlier, the couple were joined by President Katerina Sakellaropoulou and her partner Pavlos Kotsonis at the Monument of the Unknown Soldier – a memorial dedicated to Greek soldiers killed during war – to take part in the wreath laying.
On Wednesday night, Charles and Camilla were guests at an official state dinner at the presidential mansion in the Greek capital.
In a speech, the heir to the throne hailed the “strong and vital” ties between the UK and Greece, and gave a nod to his 99-year-old father’s link to the country.
The Duke of Edinburgh was born a prince of Greece and Denmark, allegedly on the kitchen table of his family home, Mon Repos, on the Greek island of Corfu, in 1921.
Speaking at the dinner, which had 45 guests in total and was hosted by President Sakellaropoulou, Charles said: “My wife and I could not be more delighted to be back in Greece, which has long held the most special place in my heart.
“After all, Greece is the land of my grandfather; and of my father’s birth, nearly 100 years ago, in the centenary year of Greek Independence.”
Charles also said he is not alone in “feeling a profound connection” to Greece, adding that “there is something of her essence in us all”.