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It's June 3rd, 1973, at the Sydney Harbor Bridge.

It's a clear day in the busiest city in Australia, and commuters are making their way to work.

But once these cars hit the bridge, they find they're going nowhere.

The reason for the traffic jam becomes clear to anyone looking up.

Between the bridge's 89-foot high pylons, the impossible seems to be taking place.

Dressed in black from head to toe, French performance artist Philippe Petit clutches tightly to the balancing pole in his hands.

He steps onto a thin rope that he hopes will support his weight.

After less than a week of planning, the high-wire trapeze artist is carrying out his plan to amaze Sydney's residents

with an illegal tightrope walk between the northern pylons of the city's iconic bridge.

It's a daring venture. Philippe has no safety net.

If he slips, he'll likely die.

The cable reacts to his first footstep with an ugly cry of metal tensing.

He pauses for a second as his pole angles to the left, threatening to take him off the line.

But he corrects his posture and then continues crossing.

The silver goals that encircle the bridge look on puzzled by the human presence so high up.

And down below, a bigger audience stirs.

To those in the cars on the Sydney Harbor Bridge, it appears as if a man is floating in the air.

Many can't believe what they're saying and stop their vehicles for a better view.

On his second journey across, Philippe stops and sits down on the wire to wave at the people below.

But the jovial mood is interrupted by the arrival of a police rescue vehicle.

Uniformed men try to get the traffic moving that they have a fight on their hands.

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