Swimmers from the original Across the Lake Swim are returning to Lake Taupo to celebrate the event turning 50.
The swim, the town's oldest continuous event, is 4.2km from Acacia Bay to Three Mile Bay.
Jubilee celebrations for Saturday's event are attracting hundreds of people to either enter or just enjoy the festivities. Some of the original 1963 participants are expected to be at the start.
The event is supported with kayakers on the water to help guide swimmers from the west side of the lake over to the eastern side. It has been organised each year by Taupo Moana Rotary Club.
Rotary member and organiser Josh Edlin said he was looking forward to the half-century celebrations.
"We've put together a retro theme. And, at Three Mile Bay where swimmers finish, there's plenty of action and entertainment for non-swimmers, families and spectators. That said, water safety is key and we hope the event can highlight water safety measures and messages."
The 4.2km swim across the lake and 1km short course finishes with a breakfast barbecue and entertainment at Three Mile Bay. This is hosted by Plunket as a fundraiser for the organisation.
The swim caters for swimmers of all ages and abilities with top swimmers vying for the race title, while others use it as a training swim ahead of Ironman New Zealand, which is held in Taupo two weeks later.
The swim is one of the events that make up the Cameron Brown, Erin Baker and Tri Taupo Awards. Late entries can be made at the Great Lake Centre tomorrow 5-7pm.
Entry is $40 for juniors (up to 15), $60 for adults, and $7 for breakfast after.