Seriously Brutal Duathlon

Caernarfon, Gwynedd

Llanberis, Caernarfon, UK

Sat 9th September 2023

Starting at 07:00

2 races

£115.00 - £190.00

Organiser's Description

This event runs along side the Triathlon set in the Snowdonia National Park. Starting in LLanberis. This is a truly awesome event and is surprisingly challenging.

There are two distances available. The half and the full.

The half starts with a lake lap run around the stunning Lake Padarn (5.2 miles) followed by a cycle ride on a challenging course with a 2 lap (58 miles) bike route around the foothills of Snowdon and then finishes with an ascent and decent to the summit of Snowdon (9.5 miles).

The full starts with 3 x run lake laps (15.6 miles) and then 4 x bike laps (116 miles) and then finishes with an ascent and decent of Snowdon (9.5 miles).


  • Seriously Brutal Duathlon - Full


    Booking for more than 1?
  • Seriously Brutal Duathlon - Half


    Booking for more than 1?


  • Seriously Brutal Duathlon - Full


    Booking for more than 1?
  • Seriously Brutal Duathlon - Half


    Booking for more than 1?

Course Details

Pick your distance
Take on the Half…

1 lap around the Lake (5m), 2 lap (58m) road bike and finish with an ascent / descent of Snowdon (9m)
Step up to the Full…

3 laps around the Lake (15m), 4 lap (116m) road bike and finish with an ascent / descent of Snowdon (9m)


The lap around the lake comes as a shock to first timers. Don’t be fooled by the description, there are plenty of hills, trails, rocks and even a waterfall to test you.


The 28 mile bike lap will certainly test you with a steep, sharp hill to start with. Then you can then enjoy the stunning views and undulating course until you reach the well known beast of a climb over Pen y Pass and super fast descent back to HQ.


Snowdon is Wales’s highest mountain and for this event you follow the Llanberis Path, which is a clear, well defined path. And if you are very lucky, you may get to experience some amazing views from the summit.


What time is registration on Friday?
Registration (which will include mountain bag kit check) is open from 16:00 till 20:00

What time is race briefing on Friday?
Half / Full Brutal briefing is 18:00

Where is registration/briefing on Friday?
In the main marquee on the event field (please do NOT bring your transition bags until the morning of the race)

Will I be given transition bags?
No, but you will be given numbered tags to attach to your own bags

Do I rack my bike on Friday?
There is NO bike racking available on Friday night. This is because of security / staffing issues

What time is transition open on race day?
From 05:00

What time/day does the race start?
All races start at 07:00 Saturday 10th September 2022

Will there be food / drinks on site?
Yes, there is a catering van open from 05:00 until late on Saturday and from 09:00 on Sunday

What will be available at the aid stations?
Torq Sports Nutrition, flapjack, cheese scones, bananas, biscuits, jellybabies, water, coke and CAKE!

Where are the aid stations?
One on the bike (mile 14) One on the run (2.5 mile approx) and one at HQ

What happens before I start the mountain section?
Before you head off to Snowdon, you will be required to check in with a medic to ensure that you are fit and well enough to climb up and back down a mountain. This check is essential but will not take more than a minute

Is there car parking available?
Please read the updated information about parking in the info pack.

Where can I stay?
There are plenty of B&Bs, hotels, campsites and bunkhouses available near race HQ. It is advisory to book early as Llanberis is a small village and it gets full very quickly

Are there showers in transition?
No, only portable toilets.

What are the rules?
Hi-viz vest to be worn on the bike AT ALL TIMES, failure to abide by this, and you will be withdrawn from the race (For all athletes on every distance). No drafting. You must wear a cycle helmet. No MP3 players or similar. No littering and you must mount and dismount at the designated points

There will be trophies awarded to the 1st, 2nd and 3rd male / female in all races.

Dinorwac Power Station works
We are aware of the planned works at Dinorwac Power Station over the next few years, but anticipate this will not impact on the race too much. Please be assured we will keep up to date with developments there.

cut offs

Half cut offs
Lake lap - 1.5 hours after start of race
Exit transition from bike to Snowdon - 6.5 hours after start of race
Overall cut off - 14 hours after start of race

Full cut offs
Lake laps - 5 hours after start of race
Exit transition from bike to Snowdon - 15 hours after start of race
Overall cut off - 21 hours after start of race

kit list

(all athletes need these items)

Issued map (waterproof pouch / bag needed)
Waterproof coat
Waterproof trousers
Extra warm clothes
A fully charged working mobile phone (water proofed) with emergency number in
Glow sticks or red tail light (Full / double / Triple only)
Survival foil blanket
Head torch (Full / double / Triple only)
More than 400ml of water or other drink
Blister kit
Soft cup - New for 2023


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Who's In

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Joel Stephens


Caernarfon, Gwynedd

9 Sept 2023

£115.00 - £190.00


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