Cardiff Marathon

Cardiff Marathon course route

The Cardiff Marathon is a mostly flat loop starting and finishing at Cardiff Castle, passing Cardiff Bay, the Principality Stadium, and Bute Park. Minor rises around the bay are the main difficulty, and spectators line the castle hub and cheer through Bute Park and along the waterfront.

Cardiff Marathon elevation profile

The Cardiff Marathon course is mostly flat with gentle undulations over 42.195 km (26.2 miles). Runners cover 138 metres of climbing and 138 metres of descent, with minimal net elevation change from start to finish.

Entry requirements

For the Cardiff Marathon, entries are managed through the official Cardiff Half Marathon website (cardiffhalfmarathon.co.uk), where marathon places are offered alongside half marathon, 10K, and team relay options during the same October festival.

Cardiff Marathon course video

Race-day footage from the course to help you picture the route, crowds, and key landmarks on marathon day.

Cardiff Half Marathon: fly over the half-marathon 3D course map!

Frequently Asked Questions

What is the Cardiff Marathon elevation profile?

The Cardiff Marathon has 138 metres of total climbing and 138 metres of descent over 42.195 km (26.2 miles). The course is mostly flat with gentle undulations, with 0 metres of net change from start to finish.

How long is the Cardiff Marathon?

The Cardiff Marathon is the standard marathon distance of 42.195 kilometres (26.2 miles), certified to World Athletics rules. Starts and finishes at Cardiff Castle.

Is the Cardiff Marathon flat?

Yes. The Cardiff Marathon is mostly flat with gentle undulations with 138 metres of total climbing over 42.195 km (26.2 miles) — a profile that suits runners chasing personal bests or Boston qualifying times.

What time does the Cardiff Marathon start?

The 2026 Cardiff Marathon starts at 10:00 am local time on Sunday, 4 October 2026. Arrive early for baggage drop and corral access — official race communications on www.cardiffhalfmarathon.co.uk/ confirm any last-minute schedule changes.

How is the Cardiff Marathon related to the Cardiff Half Marathon?

The Cardiff Marathon is part of the Cardiff Half Marathon festival weekend, sharing the same organiser and race village. The full marathon was added to give runners a longer-distance option alongside Wales' largest half marathon, which draws over 27,000 participants.

What is the Cardiff Marathon course route?

The course tours Cardiff Bay and the city centre, passing the Wales Millennium Centre, Cardiff Castle, and the redeveloped waterfront around Mermaid Quay. With around 138 metres of total climbing, it is a mostly flat course well suited to personal-best attempts.

When is the Cardiff Marathon held?

The Cardiff Marathon is typically held on the first Sunday of October, as part of the autumn race weekend. Confirm exact dates and registration at cardiffhalfmarathon.co.uk.

How do I enter the Cardiff Marathon?

Entries are managed through the official Cardiff Half Marathon website (cardiffhalfmarathon.co.uk), where marathon places are offered alongside half marathon, 10K, and team relay options during the same October festival.

Is the Cardiff Marathon a Boston Qualifier?

Yes. The Cardiff Marathon is a certified 42.195 km course and is used by UK runners pursuing Boston Marathon qualifying times, subject to the event's current World Athletics certification status.