As Paul Simon marks the 25th anniversary of his landmark 'Graceland' album, he'll also be part of this summer's Hard Rock Calling Festival in London's Hyde Park.

When Simon brought the 'Graceland' tour to the U.K. back in 1987, he sold out six shows, but it was hardly a celebration. The concerts were marked by protests accusing Simon -- who'd recorded 'Graceland' in South Africa -- of breaking the UN's cultural boycott intended to end that country's Apartheid regime.

Despite the controversy around the album, 'Graceland' sold 14 million copies and is often credited as Simon's finest work. A documentary chronicling the creation and lasting influence of the record, ‘Under African Skies,’ debuted at the 2012 Sundance Film Festival in February, and this spring, Legacy Recordings plans to release a ‘Graceland’ 25th anniversary box set.

Simon certainly won't shy away from 'Graceland' when he plays at the Hard Rock Calling Festival on July 15 -- word is he'll be joined on stage by South African male choir Ladysmith Black Mambazo and other regional musicians who appeared on the album.

Watch the Trailer for 'Under African Skies'

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