They didn't have a hope of starting a singalong, but Sigur Rós still pulled the largest crowd at Latitude. The Icelandic band, who sing either in their native tongue or in an even stranger-sounding, made-up language, may have breached the British Top Ten for the first time in their 14-year career with their current album Með Suð í Eyrum Við Spilum Endalaust, but as festival headliners they arrived on stage with scant experience.

They did bring along a splendid collection of gigantic globe lanterns, which were suspended above them, and enough dry ice to turn a picturesque hillside in Suffolk into what looked like an eerie scene from an old movie. If that was the intention, the frontman Jónsi Birgisson played the flamboyant villain to perfection. Sporting silver, glittery stripes on his cheeks, with feathers protruding from the high collar of a black, buckled jacket with fringed sleeves, he sawed manically at his guitar with a bow and sang in a searing, spooky falsetto.

Did it matter that no one knew the words? Not a jot. Backed by a sumptuous band that, from old number Glósóli onwards, included a female string section in Victorian dress and, later, a brass band in white suits and matching bowler hats, Sigur Rós delivered a majestic set that was spellbinding from start to finish. Their elegant, pounding surge of othe-worldly sounds reached its peak on Hoppipolla, best known as the theme from the TV series Planet Earth, when fans could no longer resist the urge to join in and chanted ludicrous, fabricated lyrics. As confetti rained down during the aptly titled, but still utterly incomprehensible Festival, Sigur Rós had achieved what few thought them capable of - enchanting an enormous crowd outdoors in the dark.

Earlier, Elbow had been almost as bewitching, though only sporadically so in a set that was distinctly down-tempo. Each member arrived armed with a brass instrument, adding stabs to the opener Starlings, but too often the mournful majesty of songs from their current album, The Seldom Seen Kid, teetered towards morose. One exception was Grounds for Divorce, which sounded like Crosstown Traffic mixed with Sledgehammer-era Peter Gabriel, in which the frontman Guy Garvey banged what looked like a piece of lead piping with a stick. Garvey lacked a little in the charisma department - he seemed like a lovely bloke, but wasn't convincing as a star. At least not until the closing number, One Day Like This, a string-drenched, orchestral epic that may well have been the weekend's highlight. If Garvey ever needs an ego boost, he should listen back to that track and the army of admirers who howled along.

Less lucky were the acts who played in Latitude's tents. Or rather, their fans. The weather held out for most of the weekend, but there was one continual criticism: the tents were too small. Anyone wishing to see an act had to save a space early, and plenty were left disappointed.

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