It's the day Sydney Harbour becomes one of the world's great sporting arenas.

Except there are no seats, no security and practically no limit to how close you can get to the action.

The great Sydney to Hobart yacht race began for the 63rd time and thousands upon thousands of spectators, as they do every year, came to the party.

Sydney's big wet kindly disappeared momentarily and the sun came out, bringing with it huge crowds that crammed into every available spot on the foreshore.

Those keen for a closer view of the action hit the water themselves in a plethora of crafts including small yachts, ferries, speed boats and even jet skis - all jostling for a glimpse of the spectacular race start.

The 82-strong fleet, including big boats and battlers, circled the starting line as the crews made their last-minute adjustments and ensured all was in readiness.

From up close, those on board the super maxis - Wild Oats XI, Skandia and the sleek, intimidating UK yacht City Index Leopard seemed remarkably calm - as if content that all the hard work had been done in the days, weeks and months leading up to the race.

As 13 helicopters hovered above, the starting cannon was fired by 80-year-old Michael York, the longest-serving member of the Cruising Yacht Club of Australia who has sailed the bluewater classic 15 times.

Among the fleet, he farewelled his son Andrew, heading south for the fifth time aboard Queensland entrant Alacrity.

Within five minutes, the usual suspects had broken from the field with Wild Oats XI - vying for its third straight line honours - edging out early leader Leopard.

And as the real racers went about their business the chaos carried on around them, with the spectator boats powering alongside and swarming in and out in a bid to keep up and maintain the best view.

The brave amateur skippers carried on to the heads, joining those who had been waiting there all day, to see the fleet turn south.

There were plenty of near misses and craft that looked well out of their depth, but those who fought it out were rewarded with the spectacular close-up view of the boats launching an array of bright, colourful spinnakers as they headed out to sea.

Some held on for dear life, while others did it all with a beer in hand.

It was all over in just over half an hour, but as the fleet led by Wild Oats disappeared down towards the south coast, it felt like the party was just getting started on the harbour.

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