Join us for the Metric 100-Kilometre Centurion Triathlon or the shorter Legionnaire event.


The Centurion Triathlon is based at the Fambridge Yacht Station in North Fambridge in Essex.

We have several choices for you, the Centurion, the Legionnaire at half the distance and the AquaBikus!



Cut off - 1 hr 10 minutes after the start

Please note this is a tidal river swim and will be more challenging than a typical open water or pool swim. Wetsuits are likely to be compulsory and the Swim Cut-Off is strictly 1 hour 10 minutes after the start time.

The swim distance is two laps of a 950m loop for a total of 1.9km for the Centurion distance and one 950m lap for the Legionnaire. The swim takes place next to Blue House Farm Nature Reserve on the River Crouch.

Legionnaires will complete one lap of the course for their 950m swim.




Cut off - 7 Hours after start

Helmets in place, as Centurion combatants follow the 87km cycle course that takes you out of North Fambridge and left onto Lower Burnham Rd, where you’ll enjoy a fast 10k ride out and back to South Woodham Ferrers. Passing North Fambridge again you’ll head out to Burnham-on-Crouch before starting two laps around the quite roads of the Dengie peninsula. You will experience a fast and flat course over the marshes, interspersed with a few short, sharp climbs, before returning to North Fambridge.

The Legionnaires will undertake a fast 40K Bike course as an out and back on to Southminster.

Centurion bike course

Legionnaire Bike Course

Run Course

The Run course is situated around North Fambridge Village and Centurion combatants will complete two laps of the course for their event. Spectators will have plenty of opportunity to enjoy the run stage of the triathlon while the athletes are completing their 15km run..

Legionnaires will complete a single lap of the run course totalling a 7.5km run.

Run Course Map

Quick Event Info

Centurion Tri
Imperial 100 Mile: 1.25-Mile Swim, 84-Mile Bike, 15-Mile Run
Metric 100K: 2Km Swim, 82Km Bike, 16Km Run
Legionnaire Sprint 750m Swim, 20.3Km Bike, 5Km Run
NB: Please check venue pages for exact distance options available at each
Organiser: ActiveTrainingWorld
Race Info: