On its 50th anniversary as a concert and entertainment venue, London's Roundhouse has interviewed Nick Mason about Pink Floyd's appearance as part of the legendary 1966 opening night.

The event was an 'All Night Rave' - the official launch of 'underground' newspaper the International Times, on October 15th that year, and amongst the performers were the Floyd and The Soft Machine, alongside steel bands, a drag ball, costumes, jelly and much more. Attendees were urged to "Bring your own poison, bring flowers & gass filled balloons". There was also a "SurPRIZE for shortest & barest"...

The event quickly became a thing of legend, although Nick was able to dispel some of the rumours, despite quipping "Well obviously I can't remember a thing, so I'll have to invent it for you." Despite the well-maintained, modern concert venue it has become today, back then things weren't quite so luxurious. "It had fallen into disuse. There was no lighting and no power as far as I remember. We actually had to bring in a 13-amp extension lead from some building just outside. Every now and again the power would overload and all sound would be lost while someone went to reset the fuse."

As events go, it dramatically exceeded expectations. "It was one of those things where they expected a hundred people and a thousand turned up. Certainly [Blow-Up director] Michelangelo Antonioni was there and a number of other luminaries of the time. I think Paul [McCartney] was there. There's a bit of confusion because the more likely candidate would have been John [Lennon], but yes, Paul did come down."

Nick also tries to recall Joel Brown's light show projected over the band and the stage backdrop. "Whatever we did would have been unbelievably small time. This was our first actual real gig to more than 50 people. Apart from anything else the power coming in wouldn't have been sufficient to do very much more than a couple of amplifiers and a very modest PA system… almost any band now would have far more."

To read the full interview, visit 50.Roundhouse.org.uk.