Sumarpo
Nene Valley Swimrun Festival
Sibson Lake,
31 Great North Rd, Stibbington
PE8 6LS
Saturday 7th June 2025
5k Fenland Runner Intro Solo Swimrun
PRE RACE SUPPER
Sunday 8th June 2025
Sprint 10k Monkey Sox Solo Swimrun
Half 21k Swim Secure Solo Swimrun
Half 21k Swim Secure Team Swimrun
Full 31k Precision Hydration Solo Swimrun
Full 31k Precision Hydration Team Swimrun
Saturday brings our 1st swimrun of the season in the Fenland Runner Intro 5k race.
The epic sprint 10k solo, Half 21k solo, Half 21k team, Full 31k solo and Full 31k team Swimrun races are early on the Sunday.
All are welcome to join us for our pre race Supper at 7pm on Saturday!
We are extremely fortunate to have the kind support from from Castor Parish Council, Alwalton Parish Council, Stibbington Parish Council, Yarwell Parish Council, Yarwell United Charities, Elton Hall, Sutton Parish Council Elton Parish Council Fotheringhay Parish Council Nassington Parish Council, Wansford Parish Council and all the local landowners. Without their support we just wouldn't have such an amazing course through all this beautiful countryside and local villages.
The swimming for all distances is on the beautiful River Nene.
The run sections for the 5k and 10k are predominantly flat, off road with tracks, field and compact trail. The run sections for the 21k and the 31k are more undulating and take you down in the valley on a scenic but challenging river adventure with upstream and downstream swimming on the most beautiful and clean sections of the River Nene.
Our Intro 5k Swimrun race consists of approx.
1125m of open water swimming and 3910m of mixed terrain running. 4 swim sections 5 run sections. Longest run 1800m Longest swim 500m
Our Sprint 10k Swimrun race consists of approx.
2155m of open water swimming and 7850m of mixed terrain running 5 swim sections 6 run sections. .Longest Run 3000m. Longest swim 700m
Our Half 21k Swimrun race consists of approx.
4430m of open water swimming and 17550m of mixed terrain running. 7 swim sections 8 run sections. Longest run 4000m. Longest swim 1775m
Our Full 31k Swimrun race consists of approx.
6000m of swimming and 25000m of mixed terrain running. 11 swim sections 12 run sections. Longest Run 4800m. Longest swim 1000m
SCHEDULE
(subject to change)
Saturday 7th June
**Race Safety Brief for the 10k, 21k and 31k is in your Racebook for those unable to attend this brief.
It is a Mandatory Requirement to read the Racebook or attend this safety briefing.
Sunday 8th June
PRICING
From the 30th April £175

From the 30th April £350
No extra fees at checkout
THE COURSES
5k Solo Swimrun Course
Saturday 7th June 2025
Start time 1630hrs
Splits
Run 1 400m
Swim 1 500m downstream
Run 2 800m
Swim 2 275m downstream
Run 3 860m
Swim 3 150m
Run 4 1800m
Swim 4 200m
Run 5 50m
Course Details
Distance 5.116 km
Ascent/Descent 5 m / 6 m
Uphill 1.08 km (21.1%
Downhill 0.81 km (15.8%)
Flat 2.97 km (58.1%)
Height Gain 4 m
Steepest Uphill +0.7% (at 0.00 km)
Steepest Downhill -1.1% (at 0.27 km)
Longest Uphill 0.81 km (at 3.24 km)
Longest Downhill 2.97 km (at 0.27 km)
10k Solo Swimrun Course
Sunday 8th June 2025
Start time 1100hrs TBC
Splits
Run 1 400m
Swim 1 750m upstream
Run 2 2500m
Swim 2 150m downstream
Run 3 3000m
Swim 3 700m upstream
Run 4 1100m
Swim 4 275m upstream
Run 5 800m
Swim 5 280m upstream
Run 6 50m
Course Details
Distance 10.066 km
Ascent/Descent 26 m / 26 m
Lowest Point 6 m (at 6.39 km)
Highest Point 13 m (at 6.12 km)
Uphill 1.71 km (17.0%)
Downhill 1.71 km (17.0%)
Flat 6.57 km (65.3%)
Height Gain 7 m
Steepest Uphill +4.4% (at 5.94 km)
Steepest Downhill -4.4% (at 0.36 km)
Longest Uphill 2.52 km (at 6.39 km)
Longest Downhill 0.99 km (at 2.88 km
Splits
Run 1 4650m
Swim 1 950m upstream
Run 2 2180m
Swim 2 400m downstream
Run 3 2400m
Swim 3 950m upstream
Run 4 2250m
Swim 4 950m downstream
Run 5 1100m
Swim 5 350m downstream
Run 6 3600m
Swim 6 250m downstream
Run 7 50m
Course Details
Distance 21.738 km
Ascent/Descent 76 m / 75 m
Uphill 6.75 km (31.1%)
Downhill 6.21 km(28.6%)
Flat 8.64 km (39.7%)
Height Gain 30 m
Steepest Uphill+3.3% (at 1.08 km)
Steepest Downhill-5.2% (at 2.43 km)
Longest Uphill 2.70 km (at 18.63 km)
Longest Downhill 1.62 km (at 4.32 km
Water/Aid Stations at 7.8k and 15.8k
Cut off into any water at 1300 hrs
Full 31k Solo & Team Swimrun Course
Sunday 8th June 2025
Start time 0800hrs
Splits
Run 1 4600m
Swim 1 950m upstream
Run 2 2180m
Swim 2 400m downstream
Run 3 2400m
Swim 3 950m upstream
Run 4 2550m
Swim 4 950m downstream
Run 5 1100m
Swim 5 350m downstream
Run 6 3600m
Swim 6 700m upstream
Run 7 2700m
Swim 7 175m downstream
Run 8 3800m
Swim 8 700m upstream
Run 9 1400m
Swim 9 285m upstream
Run 10 975m
Swim 10 30m
Run 11 50m
Course Details
Distance 31.240km
Ascent/Descent 131 m / 132 m
Uphill 12.60 km (32.4%)
Downhill 13.05 km (33.6%)
Flat 13.05 km (33.6%)
Height Gain 29 m
Steepest Uphill+2.7% (at 3.15 km)
Steepest Downhill-3.8% (at 2.25 km)
Longest Uphill 2.70 km (at 5.85 km)
Longest Downhill3.15 km (at 33.75 km
Cut off at
23.2k (Wansford Bridge) 1200hrs.
27k (NVR Station Crossing) 1330hrs.
Cut off Into the water at any point at 1530hrs (7.5hrs total time to complete the course)
Water/Aid Stations at 6.5k, 9.8k, 15k, 24k, 32.3k and at the finish
Camping
Camping is available at this venue please book below