The Roundhouse is a Grade II* listed former railway engine shed in Chalk Farm, London, which has been converted into a performing arts and concert venue. It was originally built in 1847 as a roundhouse, a circular building containing a railway turntable, but was only used for railway purposes for about a decade. After being used as a warehouse for a number of years, the building fell into disuse just before the Second World War. It re-opened twenty-five years later, as a performing arts venue, when the playwright Arnold Wesker established the Centre 42 Theatre Company and adopted the building as a theatre.
More information on the Wikipedia page [1]. The website is [2].