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Cardiff Half Marathon

Cardiff Half Marathon takes place on Sun, Oct 4, 2026 in Cardiff, United Kingdom. The main route is 21.1 km.

Date
Sun, Oct 4, 2026
Start
Cardiff 🇬🇧
Distance
21.1 km
Climbing
61 m
Level
Open to all
Add race day to your calendar

The Cardiff Half Marathon features a predominantly flat and fast course taking runners past the capital's most iconic landmarks, historic buildings, and scenic waterfronts.

Official event page

What this race demands

The Cardiff Half Marathon requires sustaining a steady aerobic pace over a flat 21.1-kilometer road course.

Aerobic endurance

Covering the half marathon distance of 21.1 kilometers requires sustained cardiovascular output without extended periods of relief.

Pacing discipline

The predominantly flat profile of the course encourages an aggressive early pace, requiring strict discipline to avoid premature fatigue.

What would it take you?

Pick the level closest to yours for an estimate of finish time on this course and the training a solid preparation needs.

Estimated finish

1:502:15

Peak-week training

5–7 h/week

A model estimate from distance, climbing and level, not a promise. Conditions, drafting and pacing move it.

IntervalCoach turns those weekly hours into a concrete plan built around your actual fitness. Start with this race as your goal

Your road to race day

Race day at Cardiff Half Marathon is 6 weeks away. This is how a coach divides that time. The first phase starts now.

  1. 01Peak3 weeks · Aug 24, 2026 Sep 13, 2026

    The hardest weeks of the plan: race-specific intensity at nearly full training load, sharpening exactly what this race asks for.

  2. 02Taper2 weeks · Sep 14, 2026 Sep 27, 2026

    Volume drops while intensity stays: short, sharp efforts keep the legs awake as fatigue drains away.

  3. 03Race week1 week · Sep 28, 2026 Oct 4, 2026

    Openers, rest and logistics. The work is done; the job now is arriving fresh.

Get this plan built around your own fitness

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