Wilton's Music Hall, Graces Alley, Tower Hamlets: Wilton's music hall is the only remaining example of a first-generation grand music hall in the world. It is hauntingly atmospheric, with a pervading aura of romantic decay, which presents a real conservation challenge. In 1850 John Wilton acquired the building – made up of a pub and concert room – and the neighbouring properties and constructed a much larger hall. It's alleged that Wilton's was the scene of the first London display of the cancan after which it was immediately banned. The entrance hall is simply the enclosed paved yard of the original tavern. A narrow staircase leads to a warren of small supper rooms tainted with the aura of scandalous liaisons. But the main hall is one of London's hidden wonders – a long, thin auditorium with an elliptical barrel-vaulted ceiling. Around three sides is a gallery carried on barley sugar columns with the balcony decorated with cartoon papier machePhotograph: Derek Kendall