2026 Eden Project Marathon - Oct 18 Countdown

Q: What is the Eden Project Marathon route?

The Eden Project Marathon starts and finishes at the Eden Project near St Austell, Cornwall, and runs a single multi-terrain loop through woodland, reclaimed china-clay land and open Cornish countryside. The signature feature is the climb up Helman Tor, a granite outcrop criss-crossed by muddy trails, and the dramatic finish: the last half-mile zig-zags down the side of the clay pit to end right beside the iconic biomes. It is roughly 70% on trails, paths and private roads and 30% on public roads.

Q: Is the Eden Project Marathon flat? How hard is it?

It is not flat - it is a genuinely tough, hilly multi-terrain marathon. The route packs in roughly 780m (about 2,500-2,600 ft) of total ascent, including the climb over Helman Tor and a notably steep hill around mile 23. Combined with the off-road surface, most runners finish 20-30 minutes slower than their road-marathon time. Plan your effort with our pace calculator and study the climbs with our elevation profile tool.

Q: How much climbing does the Eden Project Marathon have?

The course climbs roughly 780m in total - about 2,500-2,600 ft of elevation gain - over its 26.2 multi-terrain miles. The biggest single test is the ascent of Helman Tor, with a further sharp climb late in the race around mile 23. There is no single mountain pass; it is the relentless undulation across clay-country uplands and the trail surface that make it a difficult marathon.

Q: What surface is the Eden Project Marathon and what shoes should I wear?

The course is roughly 70% off-road - a mix of woodland trail, grassy and stony paths, reclaimed clay-pit ground and private roads, with about 30% on public roads. It can be muddy and slippery in places, especially over Helman Tor. Trail shoes are the safer, more confident choice for the grip you need on the off-road climbs and descents, particularly in wet October conditions.

Q: What time does the Eden Project Marathon start and what is the cut-off?

The marathon starts at 9:30 on Sunday 18 October 2026 from the Eden Project. There is a strict overall cut-off of 5 hours 30 minutes, enforced by interim checkpoints - around 1 hour 30 at 7 miles, 2 hours 55 at mile 13 and 3 hours 30 at mile 17. If you are outside those times you may be asked to stop, so this is a marathon to train for rather than walk. A half-marathon runs on the same day.

Q: How do I enter the Eden Project Marathon 2026?

Entry is open to the public online (no ballot) via the official entry page. The early-bird £43 tier has sold out, so the current price is the £48 full-price entry — it will not drop again, and entries close on 30 September 2026 or sooner if the capacity-capped field sells out. As Cornwall's biggest running event it does fill, so book ahead for the 18 October 2026 race. You can also secure a free place through the Run for Eden charity route by committing to raise £250.

Q: Is the Eden Project Marathon a Boston Qualifier?

No. Because it is a multi-terrain, largely off-road course over Helman Tor and clay-country trails rather than a UK Athletics road-certified, accurately measured road race, an Eden Project finish is not valid for Boston qualifying (BQ) or a London Good For Age (GFA) entry. Come for the scenery and the challenge, not a PB. If a qualifying time is your goal, check the standards with our Good For Age tool and pick a fast, flat road race instead.

Q: How do I get to the Eden Project Marathon, and where do I stay?

The Eden Project sits just outside St Austell in mid-Cornwall, near the south coast. Most runners drive, with parking on site; the nearest mainline station is St Austell (London Paddington direct, then a short taxi or bus to Eden), and Newquay airport is close by. Accommodation around St Austell, the clay-country villages and the coast at Charlestown and Mevagissey is plentiful, but book early for an October race weekend.

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Race Information

Race	2026 Eden Project Marathon - Oct 18
City	St Austell
Date	2026-10-18 at 09:30
Field Size	~200 runners
Time Limit	5 hours 30 min
Cutoff pace	7:49/km
Timezone	Europe/London
Official Site	Eden Project with St Austell Running Club

Race Day Weather

Average Temperature	13.4°C / 56°F
Humidity	85%
Wind	33.6 km/h
Rain Chance	55%
Typical Conditions	A mild but often wet, breezy October morning in mid-Cornwall. Expect around 13-14C (55-57F) at the 9:30 start, climbing only into the mid-teens, with high humidity and a real chance of rain or showers blowing across the exposed clay-country uplands and over Helman Tor.

What to Prepare: Dress for low-to-mid double-digit Celsius and pack a light waterproof - the weather over the open clay tips and tor changes fast and there is little shelter. Trail shoes are the safer choice on muddy, grassy and stony off-road sections. Run by effort, not pace: the climbs and off-road surface will slow you well below your road-marathon time.

Based on historical averages for race week. Use our Weather Score Calculator and What to Wear Guide for personalized advice.

Wind Impact on Race Day

Wind at 33.6 km/h can affect your marathon pace by 5-15 seconds per kilometer. Headwinds slow you down exponentially — a 20 km/h wind costs more than twice a 10 km/h wind.

Calculate your wind-adjusted pace →

Race-Week Climate

Based on 20 years of race-week weather (2005-2024), MERRA-2 reanalysis

	Cooler	Typical	Warmer
Temperature	11.5°C	13.4°C	15.1°C
Dew point	7.9°C	10.9°C	13.8°C

Wet-day chance: 55% Runnability: 65/100

Data: NASA POWER (MERRA-2 reanalysis), NASA Langley Research Center

Course Profile

Course Type	Single multi-terrain loop from and back to the Eden Project, roughly 70% off-road / 30% public road
Elevation Gain	780m
Terrain	Trail
Profile	A genuinely tough, hilly multi-terrain course, not a flat road race. From the Eden Project the route winds through woodland, reclaimed china-clay land and open countryside, with the major climb up Helman Tor and a notably steep hill around mile 23, before a final half-mile that zig-zags down the side of the clay pit to finish beside the biomes - roughly 780m (about 2,500-2,600 ft) of total ascent. Expect to run 20-30 minutes slower than your road marathon time.

Prepare for 2026 Eden Project Marathon - Oct 18

Use our free training tools to get race-ready:

Running Pace Calculator — Min/km, Finish Time & Pace Chart

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Free Pace Band Generator — Printable Race Day Wristband

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Marathon Wake-Up Time Calculator — Race Morning Timeline

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Dew Point Running Calculator — Pace Adjustment Chart

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Wind Effect on Running — How Much Does Wind Slow You?

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Elevation Gain/Loss Impact Calculator

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Featured In

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Frequently Asked Questions

What is the Eden Project Marathon route?

The Eden Project Marathon starts and finishes at the Eden Project near St Austell, Cornwall, and runs a single multi-terrain loop through woodland, reclaimed china-clay land and open Cornish countryside. The signature feature is the climb up Helman Tor, a granite outcrop criss-crossed by muddy trails, and the dramatic finish: the last half-mile zig-zags down the side of the clay pit to end right beside the iconic biomes. It is roughly 70% on trails, paths and private roads and 30% on public roads.

Is the Eden Project Marathon flat? How hard is it?

It is not flat - it is a genuinely tough, hilly multi-terrain marathon. The route packs in roughly 780m (about 2,500-2,600 ft) of total ascent, including the climb over Helman Tor and a notably steep hill around mile 23. Combined with the off-road surface, most runners finish 20-30 minutes slower than their road-marathon time. Plan your effort with our pace calculator and study the climbs with our elevation profile tool.

How much climbing does the Eden Project Marathon have?

The course climbs roughly 780m in total - about 2,500-2,600 ft of elevation gain - over its 26.2 multi-terrain miles. The biggest single test is the ascent of Helman Tor, with a further sharp climb late in the race around mile 23. There is no single mountain pass; it is the relentless undulation across clay-country uplands and the trail surface that make it a difficult marathon.

What surface is the Eden Project Marathon and what shoes should I wear?

The course is roughly 70% off-road - a mix of woodland trail, grassy and stony paths, reclaimed clay-pit ground and private roads, with about 30% on public roads. It can be muddy and slippery in places, especially over Helman Tor. Trail shoes are the safer, more confident choice for the grip you need on the off-road climbs and descents, particularly in wet October conditions.

What time does the Eden Project Marathon start and what is the cut-off?

The marathon starts at 9:30 on Sunday 18 October 2026 from the Eden Project. There is a strict overall cut-off of 5 hours 30 minutes, enforced by interim checkpoints - around 1 hour 30 at 7 miles, 2 hours 55 at mile 13 and 3 hours 30 at mile 17. If you are outside those times you may be asked to stop, so this is a marathon to train for rather than walk. A half-marathon runs on the same day.

How do I enter the Eden Project Marathon 2026?

Entry is open to the public online (no ballot) via the official entry page. The early-bird £43 tier has sold out, so the current price is the £48 full-price entry — it will not drop again, and entries close on 30 September 2026 or sooner if the capacity-capped field sells out. As Cornwall's biggest running event it does fill, so book ahead for the 18 October 2026 race. You can also secure a free place through the Run for Eden charity route by committing to raise £250.

Is the Eden Project Marathon a Boston Qualifier?

No. Because it is a multi-terrain, largely off-road course over Helman Tor and clay-country trails rather than a UK Athletics road-certified, accurately measured road race, an Eden Project finish is not valid for Boston qualifying (BQ) or a London Good For Age (GFA) entry. Come for the scenery and the challenge, not a PB. If a qualifying time is your goal, check the standards with our Good For Age tool and pick a fast, flat road race instead.

How do I get to the Eden Project Marathon, and where do I stay?

The Eden Project sits just outside St Austell in mid-Cornwall, near the south coast. Most runners drive, with parking on site; the nearest mainline station is St Austell (London Paddington direct, then a short taxi or bus to Eden), and Newquay airport is close by. Accommodation around St Austell, the clay-country villages and the coast at Charlestown and Mevagissey is plentiful, but book early for an October race weekend.