KEY POINTS:
Two weeks after thousands of runners made their way from Devonport to the city via the Harbour Bridge, more than 1000 swimmers will make the crossing on Sunday.
The 2.8km race from Devonport to the Viaduct Basin, the first of five races in the Sovereign New Zealand Ocean Swim Series, has attracted many of the country's best who will, in many cases, have to switch from their comfort zone of pool swimming to the demands of open water racing.
Event director Scott Rice is pleased with the quantity and quality of the field, which includes Commonwealth Games gold medallist Moss Burmester and other proven performers Dean Kent, Corney Swanepoel and Brent Foster. Melissa Ingram and Helen Norfolk who are expected to challenge for the women's title.
"For so many reasons this [race] presents a different challenge for those of us more used to a 50m pool," said Burmester. "For a start, wetsuit swimming changes the dynamic. There is also the need for navigation.
"This race is not just about those of us at the sharp end of the race, though. Sunday will bring out many stories of achievement from swimmers of all abilities."
Well away from what will be the hectic pace at the front of the field, others will set out just to finish.
On his entry form, Dave Blackie, 73, described himself as retired not tired and will again put himself to the test as he has done in competing in ironman triathlons.
Joseph MacCullum, who last year celebrated his 70th birthday by returning to Scotland where he swam Loch Lomond both ways, will join Blackie in the race for 70+ honours.
Act MP Rodney Hide has swapped his dancing shoes for a wetsuit to join the challenge. Rosie the Labrador is back and will again pace herself across the harbour.
Rice has put a comprehensive safety plan in place.
There is a 14-minute cut-off at the first marker buoy 400m from the start. The record field will be accompanied by 52 trained lifeguards and up to a dozen Thunder Cat boats.