(DailyMail)
Mystery surrounds the identity of the pair, who were spotted on a balcony underneath the giant clock on the corner of Broadway and Bay Street at 3.30pm on Friday in Sydney, Australia.
A crowd of onlookers gathered outside the Broadway Shopping Centre opposite the tower, near the University of Sydney, but that didn't seem to put off the amorous couple.
One witness said: 'A few other people had noticed as well and when I started taking photos everyone in the area started to look up and point, laugh, grin.
'From the looks of it, the couple did seem to know they could be seen and seemed completely unfazed.'
The couple may have been students staying at the UniLodge below and had gained access to the clock tower from the roof for their risque act.
Australian newspapers are appealing for the couple to come forward.
Although not as recognisable as the iconic Sydney Opera House, the historic clock tower is one of two on top of the former Grace Brothers department store building built in 1904.
The distinctive building also features two globes above the clocks and is now home to the UniLodge hotel.
