Queen Elizabeth Hall at the Southbank Centre in London is hosting the Nelson Mandela Centenary Exhibition, which has enjoyed successful runs around the world, including six weeks at the Paris Town Hall.
Harry and Meghan enjoyed the glorious sunshine as they arrived on Tuesday, with the politics and achievements of the South African revolutionary holding special significance for both of them.
The duchess describes Mr Mandela – who died in December 2013 at the age of 95 – as one of her heroes, and the Royal Family had a close relationship with the former president.
Zindzi Mandela said that her father built up a firm friendship with the Queen, to the point that he called her Lizzie.
Prince Harry has visited a number of sites associated with Mr Mandela – from his cell on Robben Island in 2008, where he was imprisoned for 18 years, to a tour of his offices, where he met his widow Graca Machel in 2015.
Joining the royal couple at the launch of the exhibition – which traces Mandela’s journey from activist to statesman – was one of the anti-apartheid campaigner’s former inmates and his granddaughter, Zamaswazi Dlamini-Mandela.
Exhibition chairman Lord Hain – who also campaigned against apartheid – said the arrival of the exhibition in the capital held a special significance.
He explained: “London was the centre of the anti-apartheid struggle.
“It was here that Mandela’s close comrade Oliver Tambo lived, led and directed the worldwide struggle, from military operations in southern Africa to diplomatic lobbying of the United Nations.
“We thought to commemorate Mandela’s centenary there should be an exhibition in London.
“It was curated by the Apartheid Museum in Johannesburg and I asked their royal highnesses to come as he does charitable work in southern Africa and she has said before that Nelson Mandela is one of her heroes.
“So we thought it would be very, very fitting for them to be at the launch and we’re thrilled they accepted.”
The visit of Harry and Meghan – who arrived at the exhibition wearing an outfit by House of Nonie – meant the arts centre had to close one of its most popular attractions for the day.
In a statement on Twitter, it said its outdoor fountains – which have been of welcome relief to visitors during the summer heatwave – were closed “for security purposes”.
Members of the public will be able to visit the free exhibition from Wednesday and it will run from 10am to 11pm each day until 19 August.
Among the items on display are a collected works of Shakespeare smuggled onto Robben Island, complete with annotations made by Mr Mandela, along with a letter of thanks written by him to the British public following an appearance at a concert held in his honour at Wembley in 1990.