An iconic Williamstown restaurant setting is available for 21-year lease in what has been advertised as a “once in a generation opportunity”.

Hobsons Bay council is inviting expressions of interest to lease the Williamstown Dressing Pavilion and The Rotunda on the Esplanade.

The pavilion is currently occupied by Shelly’s Beach Pavilion restaurant, whose lease expires at the end of November.

The lease will also expire on The Rotunda, which operates as the Rotunda In Williamstown licensed kiosk.

Shelly’s took over two years ago after the long-established Sirens restaurant went in to liquidation to repay a tax debt and unpaid creditors and workers.

Comac property management company is managing the expressions of interest campaign, which closes Tuesday, May 23.

Managing director Michael Haddrick said the council had deliberately not advertised a rental as money was not the deciding factor.

“That’s not the key determinator here,” he said.

“The key is securing the future of those buildings and also a fit-out and an operator that’s going to be secure and around for the long journey and can really do right by those buildings.”

He said the long lease was an “incredible opportunity” for any potential operators to secure a long tenure in an iconic location.

“Now, the reason that council is prepared to offer that 21-year lease is because they want to secure the long-term future of those buildings because any tenants need to invest some fairly decent capital to get those building up to scratch from a repair point of view and from an internal fit-out point of view,” Mr Haddrick said.

“The trade-off is that, yes, we acknowledge that any prospective tenant’s got to spend significant funds but you’re going to get a long-term lease which means you get a chance to recover your money.”

The pavilion seats 400 and the rotunda about 40 on level one which as 360 degree views.

Mr Haddrick said there were currently more than 20 interested parties.