Amid the bustle of guests sweeping up in limos and porters hurrying to attention in the entrance way of the InterContinental Sydney, it is a wedding dress that catches my eye – a confection of ivory organza with a sleeveless lace bodice.

It looks out of place, if romantic, flung casually over the birdcage of an unattended porter's trolley, a heap of luggage piled beneath, but in fact it's to prove a useful metaphor of the hotel, a Sydney institution and brand celebrating its 70th anniversary this year.