The Maungatautari Mission begins with a 35km road cycle from Cambridge to the start of the run at Pukeatua.
At the car park at the end of Tari Rd, competitors pass through the gates into the enclosure and on to the mountain run.
"It is the most demanding leg of the course," said race director Richard Clark.
"While 15km doesn't sound that long, this is a very steep and technical course. The record time is around 1hr 30min, so it's not an easy run."
The short bike to the Horahora Reserve holds no surprises, but the final kayak leg should not be underestimated as competitors can face strong winds on the lake course.
Boatshed Kayaks has been running a trailer to the start of the 9km kayak course every Sunday before the event to enable athletes to prepare for the course.
"So there are no excuses not to train for this one," said Clark.
"With the race returning to the old original track, not the new easy one, we recommend that people train with a partner and take safety gear with them."
Every entrant makes a $10 donation to Maungatautari Ecological Trust to maintain the 47km pest fence that surrounds the stand of native forest.
Clark said the Mission was an achievable event for athletes of all abilities. For the elites, or advanced weekend warriors, it was a great way to test themselves before taking on the multi-day races such as the Coast to Coast or the Coromandel Classic.
This year, organisers have created a new six-person family or work team division. This is made up of two cyclists, two runners and two kayakers in a double to finish.
The new division has been created to encourage more athletes into the event.
The race finishes at The Boatshed Cafe, where the tired supporters can chill out and enjoy a coffee and some food.
It is also a great place for the athletes to share their war stories.
Maungatautari Mission
When: June 22
Where: Lake Karapiro, Cambridge
Course Description:
Leg 1: Leamington to Pukeatua - 32km road cycle
Leg 2: Tari Rd to Maungatautari School - 15km run over Maungatautari Mountain, via the old track
Leg 3: Maungatautari School to Horahora Domain - 15km road cycle
Leg 4: Horahora Domain to the Boatshed - 10km kayak from Horahora Domain under the Horahora Bridge down the lake to the Boatshed Cafe and kayak landing.
For more information visit: www.theboatshed.net.nz