Ring O' Fire is a 135 miles ultra marathon in Holyhead, United Kingdom. Distance: 217km. Elevation: 5,500m D+. Difficulty: brutal (Challenge Rating 46/100). DNF rate: 35%. Time limit: 50h. Surface: trail. Established 2010.
Ring O' Fire
Holyhead, Anglesey, United Kingdom
"Run around an entire island — 135 miles circumnavigating Anglesey along the Welsh coastal path."
A complete circumnavigation of the Isle of Anglesey — 135 miles of wild Welsh coastline with cliff paths, beaches, and constant sea wind.
The Course
A complete circumnavigation of the Isle of Anglesey off the north coast of Wales, following the Anglesey Coastal Path. Rocky coastline, sandy beaches, cliff-top paths, and farmland. Deceptively tough despite modest elevation — constant undulation and technical coastal terrain.
rolling
loop
12
220m
Runner Experience
Solid aid station network with 12 stops along the course. Standard ultra fare — food, electrolytes, first aid.
Intimate finish in a remote setting. The camaraderie of shared hardship creates deep bonds between finishers.
Race Day Weather
15°C
10° – 20°
80%
45%
Irish Sea coastal weather. Wind is constant and can be fierce. Rain likely at some point over the 36+ hour effort. Sea spray on exposed sections.
Stats & Records
2010
80
37:00:00
22:45:00
Marcus Sheraton (2022)
28:30:00
Sharon Law (2023)
Entry
£180
November
months
Lore & Trivia
The Ring of Fire traverses the entire 135-mile (217km) coastline of Anglesey — a Welsh island connected to the mainland by the iconic Menai Strait bridges. The route follows the Anglesey Coastal Path over sea cliffs, across tidal causeways, through fishing villages, and past Neolithic burial chambers that predate the Egyptian pyramids. The name references the chain of prehistoric beacons that once warned of invasion from the Irish Sea. Running the full circumference of a British island, non-stop through two nights, is a uniquely compelling challenge — the ever-present sea marking your progress as you slowly circle back to the start.
- ▸ 135 miles (217km) around the entire coastline of Anglesey.
- ▸ Follows the Anglesey Coastal Path — a designated Area of Outstanding Natural Beauty.
- ▸ The name references prehistoric warning beacons.
- ▸ Runners pass Neolithic burial chambers older than the pyramids.
- ▸ Two tidal crossings require timing — get it wrong and you swim.
- ▸ Non-stop format means running through two nights.
- ▸ Anglesey was the last stronghold of the Druids in Roman Britain.
You can always see the sea at Ring of Fire. It's your clock, your compass, and your companion for 135 miles.
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Frequently Asked Questions
How long is Ring O' Fire? +
Ring O' Fire is a 135 miles (217km) ultra marathon with 5,500m of elevation gain. The course is loop on trail terrain.
How hard is Ring O' Fire? +
Ring O' Fire is rated brutal with a Challenge Rating of 46/100 (Challenging). The DNF rate is 35%. Runners have 50 hours to finish.
How do I enter Ring O' Fire? +
Must have completed a 100-mile or equivalent multi-day event. Entry costs £180. with a maximum of 120 starters.
What is the weather like at Ring O' Fire? +
Average temperature is 15°C (range 10°C to 20°C) with 80% humidity and a 45% chance of rain. Irish Sea coastal weather. Wind is constant and can be fierce. Rain likely at some point over the 36+ hour effort. Sea spray on exposed sections.
Are crew and pacers allowed at Ring O' Fire? +
Crew access is allowed. Pacers are allowed after 80km. Mandatory gear is required.
What is the course record for Ring O' Fire? +
The men's course record is 22:45:00 set by Marcus Sheraton in 2022. The women's course record is 28:30:00 set by Sharon Law in 2023.
What is the average finish time for Ring O' Fire? +
The average finish time is 37:00:00. About 80 runners finish each year. The DNF rate is 35%.
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