Grail of Trail
Two Otter Events
The Otter TERREX Trail presented by EasyEquities takes place annually and runs in the opposite direction each year. The Otter - Classic Edition traverses East to West, starting in Storms River and finishing in Natures Valley, with the Otter - Retto Edition Running West to East, from Natures Valley to Storms River.
The 42km route features rugged Indian Ocean coastline trails, indigenous forests, river crossings, spectacular scenery and 7,000 steps on average. Every year, we host two cut-off time-graded events:
- Otter - Challenge - Fearsome 11hr cut-off
- Otter - Race - Extreme 9hr cut-off
Grail of Trail

Otter Grail of Trail
Natures Valley Start
TrailFactor of 2.0
The Otter TERREX Trail, presented by EasyEquities, has a TrailFactor of 2.0. What does this mean? Simply put, TrailFactor measures how much tougher a trail is compared to a flat road. A TrailFactor of 2.0 means the Otter could take you twice as long to finish as a road marathon.
Four River Crossings
You’ll take on four river crossings along the route, each one adding to the adventure. The legendary Bloukrans River, known for its wild beauty, includes a swim that’s both thrilling and unforgettable. Where the challenge is greatest, we’ve got you covered. Our safety team will be on site with equipment to support you, and life jackets will be available for those who need them to ensure a safe and confident crossing.

Route Profile
The full route features over 2,600m of elevation gain and around 7,000 ascending steps. You’ll take on eleven climbs with more than 50 meters of elevation gain, including three that rise over 100 meters. It’s a serious test of strength and endurance, with gradients that challenge even the fittest runners.
Pace Chart and Medal Times
Click here to plan your perfect Otter. Use the pace chart to lock in your pacing strategy, stay ahead of all on route cut-offs, and give yourself the best shot at earning the medal you’re chasing.
Otter Training
The Otter TERREX Trail, presented by EasyEquities, is no ordinary race. With over 40 km of rugged terrain, 2,400 m of elevation gain, and more than 7,000 ascending steps, it’s twice as tough as a road marathon. Whether you’ve signed up for the Race with its 9-hour cut-off or the Challenge with 11 hours to finish, smart, consistent training is key to getting across the line.
This is where the Flat Rock Endurance team comes in. The plan is led by Toni McCann, a three-time Otter winner, professional athlete, and performance coach, and backed by coaches Erin van Eyssen and Brendan Lombard, who bring deep expertise in endurance, strength, and athlete health. Together, they have developed a course-specific training plan to help you prepare confidently, regardless of your starting point. With seven months of expert support and structure, this is your roadmap to your best Otter yet.
Compulsory kit
Weather factors affect compulsory kit levels
Compulsory Kit - Level 1
Fine, mild, hot but dry
Compulsory Kit - Level 2
Cool and/or wet
Compulsory Kit - Level 3
Cold, wet and/or windy
Compulsory Kit - Level 4
Very cold, and/or heavy rain
If conditions higher than Level 3 are predicted all kit required for Level 3 is compulsory.
In this case the official race will not take place, parts of the course will be rerouted & time delays should be expected.
Cancelled Event - Level 5
High winds, flooding and/or violent storm conditions with dangerously high seas.
















