Cardiff Half Marathon: entries, the ballot and race day
A guide to the Cardiff Half Marathon - the October half from Castle Street, how the ballot works, what a place costs, and when entries open for the next one.
- Next event
- 4 October 202610:00 start
- Location
- CardiffCastle Street
- Distance
- Half marathon
- Entries
- Sold out
The Cardiff Half is the biggest road race in Wales and the one the city turns out for. The next running is Sunday 4 October 2026 at 10:00, starting on Castle Street — and it is full.
The ballot
Entry works by ballot rather than by clicking fast enough on a release date, which is a better system for a race this oversubscribed but does mean you have to plan a year out. A place cost £58 through the UK ballot and £70 through the international ballot.
The 2026 ballot has closed. If you missed it, the routes that remain are charity teams and club places, which generally surface after the ballot has been drawn.
Where it starts
Castle Street, in the middle of the city, with the castle on one side of you. For a race of this size that is an unusually central start — walkable from both stations, no park-and-ride, no car park filling at seven in the morning.
Nothing here from the start line yet
I have not raced the Cardiff Half, so this page is the practical detail rather than an account of the day. When I run it, the report will appear at the foot of this page — in the meantime the journal has the races I have run.
The course
Unlike the 10k, the half gives you a real tour of the city. Most of it is flat, especially the early section around the Cardiff Bay barrage, apart from a short sharp hill at Penarth. The second half climbs north before dropping back to the finish in the civic quarter - and the climb after Roath Park at 12 miles is the one that decides your race.
- Mostly flat, with the flattest running around the Cardiff Bay barrage early on.
- A short, sharp hill at Penarth in the first few miles.
- The climb after Roath Park at 12 miles is the killer - everything after it is downhill.
- Four hydration stations on course.
Common questions
How do you enter the Cardiff Half Marathon?
Through a ballot rather than first-come-first-served. The 2026 ballot has closed and the race is full. A place cost £58 through the UK ballot and £70 through the international ballot.
Can I still get a place for the Cardiff Half Marathon 2026?
Not through the ballot, which has closed. Charity teams and clubs generally hold places that come up after the ballot closes, so those are the routes left if you missed it.
When and where does the Cardiff Half Marathon start?
Sunday 4 October 2026 at 10:00, from Castle Street in the city centre - about as central a start as a race of this size can have, and walkable from both stations.
OrganiserRun4WalesOfficial website
Details last checked against the organiser on . Dates, prices and entry windows change - confirm before you book travel.
Sources
- Cardiff Half Marathon - official site - Run4Wales
Race reports
What the day was actually like. A race page is the standing detail; a report is one running of it, on one day, with the weather and the mistakes left in.
I have not run this one yet - or have not written it up. The journal has the races I have.