It's been an icon of Sydney's gay community for more than 40 years, a safe place where even the powerful and famous could hide out in relative obscurity (or at least until they hit the footpath outside, as former police minister David Campbell learnt in 2010) but now Ken's at Kensington, Sydney's self-proclaimed "best gay sauna", is to close.

"It is with regret I confirm that Ken's at Kensington will be closing due to the sale of the building," Ken's owner, Reiner Becker, said in a statement to Sydney's gay community.

Ken's at Kensington. Credit:Ben Rushton BGR

"Sunday, May 20, will be our last day of trading and we'd love to see our 'regulars' for a 'steamy goodbye'."

The infamous sex-on-premises venue on Anzac Parade started life in 1973 after original owner Ken "Kandy" Johnson moved into what had been the home of another Sydney gay icon, the Purple Onion drag venue.

The site was originally known as Ken's Karate Klub, then Kensington Karate Klasses, an in-joke at a time when homosexuality was still illegal in NSW to explain why there were rubber mats all over the floors and "occasional sounds of groaning" from within.

Becker said he had no plans to relocate the business to a new location and that the farewell, when it comes, will be a low-key affair.