Trails & Tarmac Summer 12 hour Back Yard Ultra
RunningBackyard
Date
Sat, 18 Sept 2027
Start
08:00
Venue
Just outside Crickhowell, Powys, Wales
Powys, Wales
Countdown
September
A backyard ultra capped at 12 hours: one gentle 4.2-mile loop, every hour on the hour, and the last lap flips and runs the other way. Stay in the game or you're out.
Key facts
01Each of the first 11 loops must be finished within the hour
02The 12th loop runs in the reverse direction
03Minimum age 17
Create a free training plan for the Trails & Tarmac Summer 12 hour Back Yard Ultra
7-day free trial, no card required
The course
One lap, on repeat
Powys · one lap
Total climb87m
Duration12hr
Start · finishOne lap · elevation
0 kmDrag map to rotate6.7 km
Weather
Mid-September, Powys
16°CTypical high
8°CTypical low
2°CColdest in 20 years
49%Days with rain
1 hIn the dark
Highs around 16°C and lows around 8°C, but it has dropped to 2°C. Rain on 49% of days.
NASA POWER data, 2006-2025, the week either side of race day
2026 results
Who finishes, and how
#RiderTimeGap
01Lund, Thea07:00:00
02Williamson, Lucy10:00:00
03Perks, Natasha12:00:00
7
Women finishers
12:00:00
Median time
Women · 2026 results, as published by the organiser.
How fast could you finish?
Get a prediction based on your recent training
Organiser
OrganiserLimitless Trails (race director: Ellen Wood)
Websitelimitlesstrails.co.uk
Instagram@limitlesstrails
Running since2025
Training
Training for the Trails & Tarmac Summer 12 hour Back Yard Ultra
We don't do generic plans. We combine deep knowledge of this race's demands with your recent training, then build a plan with you that progresses as you do.
Beina integrates directly with your existing tools to understand your current fitness, and synchronise your planned sessions.
Intervals.icuWhat a Trails & Tarmac Summer 12 hour Back Yard Ultra plan targets
Typical sessions
A sustained 12hr effort
Time on feet and fatigue resistance
Fuelling and pacing for the whole event
What your weeks look like
Typical sessions
Long runs that build time on your feet
Tempo and threshold sessions to hold race pace
Back-to-back weekend runs for fatigue resistance
Not a generic schedule
Typical sessions
Built from your current fitness and the time you actually have
Adapts every week as Beina learns how you respond
Syncs your sessions straight to Garmin and Wahoo
One clear next session, never a wall of spreadsheet
Entries open now
Get your Trails & Tarmac Summer 12 hour Back Yard Ultra plan.
7-day free trial, no card required.
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