The Festival of Endurance at Hever Castle | Castle Triathlon Series | Castle Triathlon Series

The Series

The Festival of Endurance

Hailed the most friendliest and beautiful on the tri radar, this atmospheric celebration of ‘going long’ at the iconic and stunning Hever Castle promises another exhilarating event loved by competitors and spectators alike. We’re excited to introduce the 50 Mile Ultra Run on Saturday 3rd July 2021.

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The Festival of Endurance

Sunday 4th July 2021

We are pleased to announce that the Festival of Endurance will return on Sunday 4th July 2021, with an exiting edition of the 50 Mile Ultra Run on Saturday 3rd July.

Our middle distance, Gauntlet athletes race around much of the same course as the iron distance, Bastion competitors.  Whilst these two epic triathlons battle it out, they are joined by a further 6 multisport endurance events; Aquabike, Aquathlon, Duathlon. Added to the mix of this festival of endurance are ultra and long distance runners and swimmers, making this weekend a true celebration of the art of “going long”.  Please read on for more details.

Socially Distanced Event Format

A safe way to continue racing together!

We organised a hugely successful socially distance event at Hever Castle in September 2020 for over 4000 participants and their supporters. This has given not only us, the Industry but most importantly our participants, the confidence to return to racing in 2021!.

We want to reassure all participants that we’ll continue to work closely with governments, governing bodies, venues and suppliers to ensure that our 2021 events are run in accordance with current health and safety guidance.

Our increased health and safety measures cover 5 key principles of education; touch point reduction, density reduction, athlete self-reliance and enhanced hygiene.

Should we be require to put on a socially distanced event, participants will still get the full race experience but with individual rolling starts, 1 competitor every 10 seconds (sometimes greater), restricted time on site either side of your race and possible limit on spectators per athlete only.

We will prepare venue specific documents to send to all participants ahead of the event. These will include details on how to prepare pre-event, arrival timings and movements, swim, cycle, run, festival village and exit.

The Bastion

Sunday 4th July 2021

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

Set in close proximity to London and in the heartland of Henry VIII’s old hunting grounds, each leg of the Bastion has been designed to offer the ultimate physical challenge to athletes but in the most beautiful setting. The Bastion, which were the final strongholds of medieval castles, features an iridescent 3.8km river and ornamental lake swim, a true toughie of 180km bike course with 2,700m of climbing and a 42.2km trail run that takes place largely off road and incorporates the gardens of both Hever and Chiddingstone Castles. You won’t get a personal best over this distance but you will have the bragging rights to arguably one of the toughest and most iconic races of its kind anywhere in the world.

Triathlon England National Middle Distance Triathlon Championship

Sunday 4th July 2021

1.9km/90km/21km – Middle distance triathlon.

The Festival of Endurance at Hever Castle will host the Triathlon England Middle Distance Triathlon National Championship. Want to become an English Champion? Make sure you’re eligible here.  We have been re-awarded the English Middle Distance Championships which are due to take place on the same calendar weekend, Sunday 4 July. 2021.

This middle distance course is made for a National Championship with the 1.9km swim will involve 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.

Click here for cycle elevation route
Click here for run elevation route

The 21km run course is 2 loops of 10.5km, takes in 4kms within Hever Castle ground with a 6.5km extension via tracks and bridle paths though the historic local village of Chiddingstone. The course includes a strong off road element which allows a highly inspirational setting often praised and welcomed by the elite triathletes.

The Gauntlet

Sunday 4th July 2021

1.9km/90km/21.1km – Middle distance triathlon

Those taking on The Gauntlet, previously filmed by Channel 4, swim the unique 1.9km  loop of the infamous 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 over the Ashdown Forest. The running tracks and bridle paths, passing by historic local villages, offer a strong off road element. This super-tough course may not give you a chance of PB but you will have undertaken a huge challenge of one of Europe’s most beautiful courses

The Duathlons

Sunday 4th July 2021

  • 10.5k / 45k / 4k (Laps 1:1:1)
  • 21k / 90k / 10.5k (Laps 2:2:1)

After a unique run (1 or 2 laps) through the glorious Kent countryside and around the private estates of Hever and Chiddingstone Castles, cycle up to the highpoint of the Ashdown Forest (1 or 2 laps) before finishing off with further laps of the beautifully manicured gardens and local network of paths and trails.

The Aquabikes

Sunday 4th July 2021

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

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 up through the High Weald of Kent before passing 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 Aquathlons

Sunday 4th July 2021

  • 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.

50 Mile Ultra Run

Saturday 3rd July 2021

50 Mile Ultra Run

Fully supported with 6 stocked feed stations, this is a beautiful, hilly, mostly off-road 50 miler taking in the South Downs and Ashdown Forest. Starting at Eastbourne Pier, the start of the official South Downs Way, passing Beachy Head and the rolling Seven Sisters and skimming the edge of the Glyndebourne estate, runners follow a series of footpaths along the  Sussex Ouse Valley Way all the way to the  Ashdown Forest. The descent from the forest brings you through stunning countryside  with the home run though the village of Chiddingstone and on to Hever Estate.

The Hever Marathon

Sunday 4th July 2021

26.2 miles/ 42.2k

After the huge success of the inaugural event in the 2018 Series, the marathon returns to the atmospheric Festival of Endurance at 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 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, oast houses and with spectators and locals cheering you on all the way! Marathon Pacers in attendance.

The Hever Half Marathon

Sunday 4th July 2021

13.1 miles/ 21.1k

Take on the half marathon at our 2019 Festival of Endurance, on the most stunning off road course in the UK.

Starting at the drawbridge of the Hever Castle, this two-lap course takes in two castles, two lakes, quaint Kentish villages, oast houses with spectators and locals cheering you on all the way! Finish your race with a big celebration, medal and finishing line banquet in sight of the castle. Half Marathon Pacers in attendance.

The Hever Long Distance Swim

Sunday 4th July 2021

  • 10K Marathon Swim  Entry tickets also available a relay team of 5 (each team member takes on the 2k loop circuit).
  • 3.8k Swin
  • 1.9k swim

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.

Hever Cycle Sportives

Saturday 3rd July 2021

  • 180k Cycle Sportive
  • 90k Cycle Sportive

The inaugural Festival of Endurance (FOE) cycle sportive is a wonderful amalgam of a number of recognised local cycling route classics.

The 180K circuit takes in 12 category 5 climbs and scales a massive 2,291m of ascent and the 90K circuit takes in 6 category 5 climbs and scales a an impressive 1,187m of ascent.  The first 12K and the last 32K follow the existing Bastion (full iron distance triathlon) 60K loop but everything else is virgin FOE territory.

Scroll down for GPX routes

To compete in the Hever Castle Triathlon you can enter either as an individual, a relay team of two, or a relay team of three. Relay entries can be all male, all female or mixed.

Saturday 3rd July 2021

Race Name
Race Distance
Race Price
(Individual / Relay)
Discount Prices
(Individual / Relay)
Start time
The 50 Miler
50 Miles
180K Cycle
90K Cycle

*Approx Timings: This event is currently set up for socially distanced format, whereby we will adopt a rolling start. Therefore the above timings represent the time the first person sets off in that particular distance. These are approximate timings and are only to be used as a guide at this stage. [27/4/21]

Sunday 4th July 2021

Race Name
Race Distance
Race Price
(Individual / Relay)
Discount Prices
(Individual / Relay)
Start time
Full Iron The Bastion
3.8km / 180km / 42.2km
£360 / 450
£324 / £405
Swim Marathon
10K Swim
£80 / 135
£72 / £122
Half Iron The Gauntlet
1.9km / 90km / 21km
£220 / 270
£198 / £243
^Aquabike Middle (Swim / Bike)
1.9km swim / 60km bike (optional 4km run)
^Aquabike Long Distance (Swim / Bike)
3.8km swim / 120km bike
Aquathlon Middle (Swim / Run)
1.9km swim / 10.5km run
Aquathlon Long (Swim / Run)
3.8km swim / 21km run
Middle Distance Swim
1.9km swim
Long Distance Swim
3.8km swim
Duathlon Long (Run / Bike / Run)
21km / 90km / 10.5km
Duathlon Middle (Run / Bike / Run)
10.5km / 45km / 4km
Full Marathon
42.2km run
Half Marathon
21.1km run

*Approx Timings: This event is currently set up for socially distanced format, whereby we will adopt a rolling start. Therefore the above timings represent the time the first person sets off in that particular distance. These are approximate timings and are only to be used as a guide at this stage. [27/4/21]

Relay options apply for 10K Swim, Gauntlet and Bastion competitors.

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

^The Aquabike includes an optional 4km run.

The 50 miler, begins at Eastbourne pier.

Course maps

Please take a moment to study these in details.

The Festival of Endurance at Hever Castle is an exciting and busy event with lots of different courses taking place throughout the day. There will be a full brief before your race start but it’s a good idea to familiarise yourself with the course and in particular any key junctions to ensure you take the correct route.

Race day information

Two weeks prior to event, this section will give you everything you need to know about race day, including wave times, registration opening details, spectator entry, camping info and water temperature readings etc.

Results and photography

Find the  Races Results from previous years here along with amazing shots of participant’s photography during the event.

If you have any queries please contact Stuweb Timing Solutions here.

Useful information

Race licence

The Castle Triathlon Series UK events are governed by the British Triathlon Federation and their technical officials will provide guidance on the day and in the run up to the event.

On race day, all  participants involved in a multi-discipline sport are required to produce a valid triathlon governing body membership card or purchase a Day Licence. The Day Licence must be purchased online prior to the event. Details will be sent out closer to the event.

Competitor Photography

PRE-Race day offer! AWOL Adventure photography team will be positioned around the course, finish line, and event village ready to capture that timeless photo – Just don’t forget to SMILE!

Pre-order your digital bundle of pictures for a special HALF PRICE DISCOUNT. Here’s how it works…..

ALL your Digital Photos for for half price
Min. 2 photos GUARANTEED or your money back*
Bundle goes to full price after the event so hurry!

*Click here for quick FAQ and details of Awol Adventure guarantee

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.

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.

Travel, accommodation and directions to the venue

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

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

For swim length up to 1500m wetsuits will be optional on race day if the temp remains between 14 and 22 degrees centigrade and over 1500m swim length wetsuits will be options between 15 and 23 degrees centigrade.

Useful downloads:

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; from first timers, old timers, juniors, female focus, elites, tri clubs, corporates, there’s a race for everyone!

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Trade your time for a free race place! We offer a Volunteer Scheme, whereby a free race is given in return for a day’s marshalling at any one of the Castle Triathlon Series events. (terms apply)

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