KEY POINTS:
From modest beginnings - 500 competitors for the first Harbour Crossing in 2004 - the Ocean Swim Series has expanded into a nationwide five-race series offering generous prizemoney and attracting the best New Zealand swimmers.
An international element kicks in for its fourth year with leading Australians expected to line up.
This summer's Sovereign series opener, the 2.8km swim from Devonport to the Viaduct on Sunday, is expected to have 1200 swimmers on the start line - stopping marine traffic on the Auckland Harbour as they chase the 33m 16s race record (set last summer by Kane Radford on a course slightly different from that swum and won by Brent Foster in 2004).
The race, seen by many as akin to the long-established Round the Bays race for those who want to make the journey around the waterfront on foot, attracts the elite and social swimmers to the once-a-year chance to swim across the harbour.
Safety has long been paramount with race director Scott Rice, who leaves nothing to chance.
This summer he has entered into a new partnership with Surf Lifesaving New Zealand.
"Our event is as much about communities in which we race and the overall lifestyle of New Zealanders," said Rice.
"We are blessed in this country that the vast majority of Kiwis live within an hour's drive of a beach and yet we are still not active enough as a nation nor are we safe enough at those beaches.
"Surf Lifesaving New Zealand is as much a part of Kiwi summers as Jelly Tips and jandals with lifeguards making our beaches so much safer every summer.
"Yet despite the lives they save and the great work they do, they are always looking for funding to support their great work. For us at Sovereign Ocean Swim Series this [partnership ] was an obvious fit."
The surf lifesaving body has welcomed the chance to be linked with the swim series.
"Ocean swimming, both competitive events and recreational swimming, continues to become increasingly popular with an incredible 2.3 million people visiting a beach at least once in the past 12 months," said chief executive Geoff Barry.
"We're responding to this with provision of water safety services, but also encouraging people to use New Zealand's favourite playground.
"The beach and coastal waterways are accessible to so many in New Zealand ... [it] is a natural fit with Surf Lifesaving New Zealand."