Kiwanis secretary Leigh Baker is recommending a splash and dash in the clear waters of Lake Rotoma to celebrate Waitangi Day.
He said it was a way for locals to make the most of the natural beauty of the area, as well as having fun and exercising.
"A swim for Waitangi Day makes people aware of the resource we have and maybe we should care for it and look after the ecology of the local area," he said.
The Lake Rotoma Swim has been run annually on Waitangi Day since 1979 and started with just a couple of families wanting to meet up for a regular activity on the day.
Since then the swim has blossomed to a fun day out for more than 100 people and the day has more than 20 entry options for swimmers of all ages and abilities.
"Our youngest has been 18 months old (complete with arm floats) alongside his parents to a swimmer aged in their 70s," said Mr Baker.
"It is also a great experience for teenagers who haven't been out of their depth in the water before. Unlike the sea, it's calm and they can have the experience of swimming in deep water without being panicked."
Younger, less able swimmers can swim 100m with their parents. Then the course distance jumps to 400m, 6km and the serious swimmer can swim between 10 to 15km.
The Lake Rotoma Swim is one of four events staged on Rotorua Lakes. Competitors who swim three will receive a Famously Rotorua "Swim the Lakes" T-shirt. After Lake Rotoma, competitors can then swim Lake Tikitapu and Lake Okataina later in the season.
The Lake Rotoma Swim is organised by the Kiwanis Club who use the money raised at the swim for its charity work. Kiwanis International has joined forces with UNICEF to eliminate maternal and neonatal tetanus.
* What: Lake Rotoma Swim - Kiwanis.
* Where: Lake Rotoma, State Highway 30.
* When: Tomorrow 9am-2pm.