Caernarfon 10K
Race snapshot
Race Day
54–66°F · Feels mild
Total elevation gain
Moderate rolling hills · Net elevation change +0 ft
Participants
Intimate field
Crowd Rating
Moderate spectator support
The Lowdown
The Caernarfon 10K is an annual road race organized by Club Rhedwyr Eryri Harriers, starting and finishing at Coed Helen Recreational Grounds on the banks of the River Seiont, a short walk from Caernarfon Castle in North Wales. Run under UK Athletics rules with full chip timing, the race follows what organizers describe as a 'rural scenic course' through the countryside around the Foryd estuary, taking in views toward the Menai Strait and the foothills of Snowdonia; the course is not suitable for wheelchairs, and walkers and personal headsets are not permitted. The race has run annually since at least 2017 and is typically held on a Sunday morning in early-to-mid August as part of the Welsh 10km Road Race Series, with the 2025 edition run on 10 August and the 2026 edition on 9 August; the 2027 date below is projected from that cadence and should be reconfirmed closer to race day. All finishers receive a race memento, and prizes are awarded across a range of age-category and club divisions. Race numbers and timing chips are collected on the morning of the race from 8:00am at race headquarters, ahead of the 10:00am start at Coed Helen Recreational Grounds (postcode LL54 5RP). Entries are taken online through Run Wales, with a discounted rate for runners affiliated with a club or Welsh Athletics. This is a separate, standalone event from the Caernarfon Half Marathon, a different race organized by Run Wales each September on a course that starts and finishes near Caernarfon Castle.
Questions about the Caernarfon 10K 2027
When is the Caernarfon 10K 2027?
Sunday, August 8, 2027.
Where is the Caernarfon 10K?
Caernarfon, Gwynedd, United Kingdom.
What time does the Caernarfon 10K start?
The race starts at 10:00 AM, local time.
What is the Caernarfon 10K time limit?
1 hour 30 minutes.
How do I enter the Caernarfon 10K 2027?
Registration has not opened yet. Ways in: Online via the official Run Wales event page; On-the-day entry at race HQ if online entries have not sold out.
How much does the Caernarfon 10K 2027 cost?
10K - Unaffiliated: £19. 10K - Club / Welsh Athletics Affiliated: £17.
What is the Caernarfon 10K elevation gain?
40 m (131 ft) of total elevation gain. Net elevation change: +0 m (0 ft). Moderate rolling hills.
What is the Caernarfon 10K course like?
It passes Caernarfon Castle, River Seiont and Foryd estuary and Coed Helen Recreational Grounds.
What is the weather like at the Caernarfon 10K?
Race-day temperatures are usually 12–19 °C (54–66 °F). Feels mild.
How many runners does the Caernarfon 10K have?
350 participants. Intimate field.
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