Frontman Ian Anderson once jokingly attributed Jethro Tull's uniqueness to the fact the group had always abstained from recreational drug use - although you would never have guessed this from Anderson's googly-eyed mania and psychedelic wardrobe.

Since emerging in the late Sixties, these kings of prog rock and chief exponents of the concept album have been regularly derided by the critics, but their following is massive.

Their peculiarly English mix of hard rock, folk melodies, blues licks and surreal, impossibly dense lyrics has seen the Tull shift an incredible 60 million albums and play an average of 100 gigs every year.

Although they began as a blues outfit, the band rapidly evolved into an eclectic blend of Celtic folk, rock and classical. By the time Aqualung, their magnus opus, was released in 1971, Anderson had cemented his reputation as a wildman-sage. Aqualung is essentially one long song, steeped in surreal imagery and social commentary.

With more than 30 albums under their collective belt, the band continue to release new material, albeit rather sporadically.

They have made it clear performing live is where they prefer to put their energy and this is where the music characterised by swooping, shimmering acoustic guitar lines, Ian Anderson's quirky vocals and passionate flute playing - is at its best.

Starts 7.30pm, tickets cost £24.50 and £27.50. Call 01273 709709