Everyone loves a surprise guest appearance at a festival, and revellers at this year's Newport Folk Festival were treated to none other than Mumford & Sons over the weekend as special headliners. Even better, they performed a stellar Radiohead cover that totally blew fans away.

Mumford and Sons performing live at OptimusMumford And Sons performing live at Optimus

The Rhode Island event was only the band's second live show this year, after iHeart Alterego at The Forum in January, though they do have three other festival dates to go. They certainly did themselves justice with a 15-song set on Saturday (July 28th 2018) which included some amazing covers.

Standing out most of all was their take on Radiohead's lesser-known single 'All I Need' from their 2007 album 'In Rainbows' with the help of 23-year-old LA musician Phoebe Bridgers who was also performing at the event.

They also did Simon & Garfunkel's 'The Boxer', Maggie Rogers' 'Alaska' with the singer herself, The New Basement Tapes' 'Kansas City' and The Band's 'The Weight' with Mavis Staples.

It's been three years since Mumford & Sons released their third album 'Wilder Mind', a strong departure from the acoustic sound of 'Babel' and 'Sigh No More'. They've toured plenty since then, and while we haven't seen much of them this year, that doesn't mean they haven't been busy.

Frontman Marcus Mumford has been working alongside Rage Against the Machine's Tom Morello for the latter's forthcoming solo album (the name of which has not yet been announced), and he's also on the judging panel for this year's Mercury Prize next to the likes of Mistajam, Lianne La Havas, Jamie Cullum and Ella Eyre.

Meanwhile, the band were awared the Trailblazer Award at the UK Americana Awards 2018 for their contributions to the genre of folk and Americana.

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Mumford & Sons will next perform at Sziget in Budapest on August 11th, with Ohana Festival to follow on September 30th and New Orleans' Vood Festival on October 26th.