Serious athletes seeking an unparalleled challenge should mark their calendars for September 19th, 2026, when the Seriously Brutal Duathlon takes place in Llanberis, North Wales. This race is part of the renowned Brutal Triathlons series but offers a unique twist by eliminating the swimming leg and focusing on rigorous running and cycling routes. Competitors can choose from three distance options: Bach (Standard), Canol (Half/middle), or Mawr (Full/big). Each course features an initial run around a challenging lake loop, followed by a demanding bike ride through hilly terrain, culminating in the iconic ascent of Yr Wyddfa (Snowdon). ### Course Details - Bach: 2.3 miles running lap, 29-mile road biking, and a final mountain climb/descent. - Canol: A full lake loop at 5 miles, two laps on the bike totaling 58 miles, concluding with Snowdon's ascent and descent. - Mawr: Three loops around the lake (15 miles), four laps of cycling covering 116 miles, ending similarly atop Yr Wyddfa. The running portion begins with a shock to newcomers due to its hilly trails, rocky paths, and even a waterfall. Cyclists face steep climbs early on before enjoying scenic views along undulating roads leading up Pen y Pass and back down via the Llanberis Path for Snowdon's segment. ### Race Logistics Registration opens Friday from 4 PM until 8 PM at the main marquee near race HQ, where athletes can also attend a briefing. Transition areas open on Saturday morning by 5 AM with all races starting promptly at 7 AM. Aid stations provide essential nutrition and hydration during both run and bike legs. ### Safety Measures Before tackling Snowdon, participants must check in with medical staff to confirm they're fit for the climb. This ensures everyone's safety while minimizing delays. Cyclists are required to wear high-visibility vests throughout their ride, adhere strictly to no-drafting rules, use helmets at all times, and follow designated start/stop points. ### Accommodation & Amenities With Llanberis being a small village prone to quick bookings, competitors should secure lodging early through local B&Bs, hotels, campsites, or bunkhouses. Portable toilets are available in transition areas but no showers will be provided on site. Trophies await the top three male and female finishers across all distances, adding an extra layer of prestige for those who conquer this formidable course. The Seriously Brutal Duathlon promises a blend of breathtaking landscapes, technical challenges, and camaraderie among competitors. Whether you're aiming to push your limits or simply enjoy the thrill of competition in one of Wales' most scenic settings, this event is not to be missed. For more detailed information including GPX downloads and entry fees, visit the official website.
Races Offered
The Seriously Brutal Duathlon Bach (Standard)
Sep 19, 2026
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The Seriously Brutal Duathlon Bach (Standard)
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Multisports
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20 days remaining
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£63.00
The Seriously Brutal Duathlon Bach (Standard) - Team
Sep 19, 2026
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The Seriously Brutal Duathlon Bach (Standard) - Team
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Multisports
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20 days remaining
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£81.00
The Seriously Brutal Duathlon Canol (Half)
Sep 19, 2026
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The Seriously Brutal Duathlon Canol (Half)
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Multisports
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20 days remaining
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£121.50
The Seriously Brutal Duathlon Canol (Half) - Team
Sep 19, 2026
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The Seriously Brutal Duathlon Canol (Half) - Team
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Multisports
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20 days remaining
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£153.00
The Seriously Brutal Duathlon Mawr (Full)
Sep 19, 2026
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The Seriously Brutal Duathlon Mawr (Full)
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Multisports
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20 days remaining
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£216.00
The Seriously Brutal Duathlon Mawr (Full) - Team
Sep 19, 2026
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Distance —
The Seriously Brutal Duathlon Mawr (Full) - Team
terrain
Type —
Multisports
timer
20 days remaining
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£270.00
Weather History
These values represent the 3-year monthly averages for September in Llanberis.
thermostatTemperature
11.0° / 16.7°
wb_sunnyFeels like
8.6° / 14.4°
light_mode
Avg sunshine hours
7h 11m
water_drop
Avg rainfall
7.0 mm
ac_unit
Avg snowfall
—
air
Avg wind speed
14.8 km/h (Gentle breeze)
opacity
Sweat loss rate
Low
terrain
Course conditions
Firm and slightly soft
sunny
Max UV Index
Moderate (3.5)
humidity_mid
Humidity
88.1%
wb_twilight
Sunrise
06:51
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Sunset
19:30
About Llanberis
Learn more about the host city, Llanberis.
Llanberis is in North Wales, 7 miles away from Caernarfon. It is the 'base camp' for Mount Snowdon.
