Duke and Duchess of Edinburgh visit, 640th anniversary

The Duke and Duchess of Edinburgh have begun a three-day official visit to Portugal, marking the 640th anniversary of the Treaty of Windsor, the world’s oldest diplomatic alliance. The couple arrived in Lisbon on Monday, where their engagements included meetings with local officials and the unveiling of a historic exhibition.

For her first engagement, the Duchess of Edinburgh chose a white, long-sleeved silk dress with a green clover print. The dress, by British designer Suzannah London, was one she had previously worn to celebrate her 26th wedding anniversary with Prince Edward at Royal Ascot last year. She paired the dress with gold jewelry and a white handbag for a meeting with Lisbon Mayor Carlos Moedas in a city park. Following the meeting, the mayor accompanied the couple on a tram ride through the city.

The central event of the day was the opening of a special exhibition at the Portuguese National Archive. There, the royal couple unveiled the first public display featuring both the original English and Portuguese copies of the Treaty of Windsor side by side. The treaty, signed in 1386, formalized the enduring Anglo-Portuguese partnership.