Pop-up City Triathlon
24-27 April 2017

Lough Cutra Castle
26/27 May 2018

Cholmondeley Castle
23/24 June 2018

The Festival of Endurance at Hever Castle
8 July 2018

Castle Howard
21/22 July 2018

Château de Chantilly
25/26 August 2018

Hever Castle
23/24 September 2017

Schools Roadshow
July 2017

The Series

The Festival of Endurance

Sunday 9th July 2017 promises another exhilarating and atmospheric celebration of ‘going long’ at the iconic and stunning Hever Castle. Loved by competitors and spectators alike the event is hailed the most friendliest and beautiful on the tri radar.

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The Festival of Endurance

Sunday 9th July 2017

We are pleased to announce that the Festival of Endurance will return in 2017, 9th July.

Due to popular demand, the Hever Gauntlet half-iron triathlon will be held bi-annually giving triathletes the option to race alongside the full iron-distance Bastion competitors on 9th July 2017. Whilst these hardy triathletes battle their way around this iconic course, we shall host a further three challenges for those looking for an opportunity to ‘go long’.  Please read on for more details.

The Bastion

3.8km/180.2km/42.2km – Full iron distance race.

Set within close proximity to London and triathlon’s heartland of the south-east, each leg of The Bastion has been carefully designed to offer the ultimate challenge for both newcomers to long-distance triathlon and experienced long-course hands. The Bastion, the final stronghold of a medieval castle, will feature a 3.8km river and lake swim, a true toughie of a 180km bike course with 2,000m of climbing and a 42.2km run course that takes place largely off-road including the beautiful grounds of Chiddingstone Castle. Following a huge success in 2014 generating rave reviews, the iron distance men and women enhanced the experience in 2015 contributing to growing this event into one of the truly iconic long distance triathlons in the world.

The Gauntlet

1.9km/90km/21km – Half iron distance race.

The Gauntlet returns to Hever Castle In July after the success of the September races. The 1.9km swim is a single loop taking in the main Hever Castle lake and a tributary of the River Eden. The 90km cycle (2 loop course) winds its way through the stunning High Weald of Kent and the Ashdown Forest. The 21km run course (2 loops of 10.5km), follows largely off-road tracks and bridle paths between Hever Castle, through the historic local village of Chiddingstone.

Long course training distances

We are offering you the chance to swim ,bike or run sections of the Bastion course, fully timed and fully supported just like those taking on the iron-distance race alongside you.

The perfect training to prepare for any iron-distance challenge or to get an idea of what might await you next year should you return for the ultimate Castle Triathlon Series challenge and take on The Bastion in 2017. This is a fantastic long distance swim training and long distance race tri training set in a stunning location in mid-summer, perfect for those who are taking on an iron-distance race in the second half of 2016.

The Marathon

26.2 miles

We are excited to announce that the atmospheric Festival of Endurance will host its first marathon in 2017 at the iconic Hever Castle.

Forget the city marathon, and fill your lungs with country air and stunning scenery before you conquer your marathon by a Castle drawbridge. This new marathon, promises the most stunning on and off road course in the UK, a truly motivational and beautiful route that will distract you from the challenge itself. The four-laps take in two castles, two lakes, quaint Kentish villages with oust houses and castle grounds with spectators and locals cheering you on all the way!

Half Marathon

13.1 miles

You can take on a two lap half marathon at our 2017 Festival of Endurance, on the most stunning on and off road course in the UK.

The run, two loops of beautiful countryside takes in two castles, two lakes, quaint Kentish villages with oust houses and castle grounds with spectators and locals cheering you on all the way! And there is a big celebration with medal and finishing line banquet as you cross the finishing line in sight of the drawbridge.

The Aquabike Challenge


  • 1.9k swim: 60k cycle: 4k optional run (Laps 1:1:1)
  • 3.8k swim: 120k cycle: 4k optional run (Laps 2:2:1)

There’s a training option for everybody who’s into long distance.  After the unique swim you’ll head out on the fully marshalled and signed bike course with supported feed stations. This circular cycle route will take competitors out of Hever Castle, up through the High Weald of Kent before passing through and over the Ashdown Forest and into the village of Maresfield.  After a quick tour of the village competitors retrace their steps to the top of the forest before returning to Hever via the historic and quintessentially English villages of Groombridge, Fordcombe and Penshurst.  Finishers have the option of finishing with a gentle 4K run that circumnavigates the lake and stunning grounds of the Hever estate.

The Aquathlon Challenge


  • 1.9k swim / 10k run (Laps 1:1)
  • 3.8k swim / 21k run (Laps 2:2)

After the unique swim (1 or 2 loops), competitors will then embark on the 10k/21km run course, which follows largely off road tracks and bridle paths between Hever Castle, through the historic local village of Chiddingstone, before finishing right in front of the Castle.

The Hever Long Distance Swim


  • 1.9k circuit
  • 3.8k circuit

The swim course leaves from the Italianate loggia taking competitors down the length of the main lake and heading into the scenic river section.This tributary of the River Eden wraps around 16 Acre Island allowing spectators to watch and cheer competitors on from only a few meters away. The Speedo team will be on hand to welcome you at the finish, then it’s time to relax and enjoy a complimentary bacon roll back at the Event Village.

2017 Race distances and pricing

Race Name
Race Distance
Race Price
(Individual / Relay**)
Start time
The Bastion Iron Distance
Long Distance Aquabike
3.8km swim / 120km bike (optional 4km run)
Middle Distance Aquabike
1.9km swim / 60km bike (optional 4km run)
The Gauntlet Half Distance
Long Distance Swim
3.8km swim
Middle Swim
1.9km swim
Long Distance Aquathlon
3.8km swim / 21.5km run
Middle Distance Aquathlon
1.9km swim / 10km run
Half Marathon
21.1km run
Full Marathon
42.2km run

*Start times are approximate and shown here as a general guide. These are subject to change. Each distance start time is preceded by a brief by the Race Director.

**Relay options apply for Gauntlet and Bastion participants.

Entrants will be notified via email with full race details, including confirmation of wave times, 2 weeks prior to the event.

Useful information

Preparation for the event

The 2017 Competitor Guide, tailored for the Festival of Endurance at Hever Castle guides the competitor through the preparation for the event.

FOE Competitor Guide 2017
Spectator Offering

The spectator experience at the Castle Triathlon Series has become almost as famous as the spectacular backdrops and classic courses, and has made passing time before your loved ones finish the race a thing of the past.

Travel, accommodation and directions to the venue

Click the link below to find out everything you need to know about all of our venues.

Rules and Terms and Conditions

Please read and understand the general rules, in particular the cut-off times, before competing to ensure a fantastic race for you and everyone else.

Water quality

Please see the latest water quality tests for Hever Castle lake. All tests are undertaken using the EU Water Bathing Directive as the benchmark.

Water temperature

This will be taken nearer the Event, and posted on the Race Admin page.


Race distances

Race distances

For the absolute beginners and children to the professional triathletes, the Castle Triathlon Series offers a wealth of race distances to suit all levels.

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Hosted at a selection of stunning and iconic castles across the UK, Ireland and France, the Castle Triathlon Series events all promise an inspirational and memorable race experience.

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Take part

We pride ourselves on offering a bespoke and tailored offering for all those wishing to take part and grateful for all those who want to be involved on the day.

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We would always recommend training in preparation for any event, but how much you do, and the style you take is down to you.

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