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Sailing ships moored in Hoorn's old harbour beneath the Hoofdtoren and a row of gabled houses.
Race Finder

IRONMAN 70.3 Westfriesland.
Your best day in Hoorn.

A busy start in Hoorn’s old harbour. A flat, open 90 km where the wind sets the speed. Then two and a half loops through the old town and along the water.

Hoorn’s old harbour and the Hoofdtoren.

Race day
20 Jun 2027
Course
Swim 1.9 km · Bike 90 km · Run 21.1 km
Historical air
15–24°C

What could you race?

I’m Tom, the coach behind Sense Endurance Coaching. Tell me where you are now and I’ll show you what a strong day in Hoorn could look like.

Let’s build your race

Let’s build your race.

Your age and race category help me estimate where that performance could place you. They don’t determine how fast I think you can race.

Change units

Open roads test your pacing before Hoorn tests your run.

A course can look fast while still punishing athletes who try to force speed through changing conditions. The useful advantage is preserving decision quality until the final part of the run.

The harbour start · first 300 m

Leave the harbour without a fight.

The old-harbour start will feel busy. Your first win is finding clear water and a rhythm you can keep, not proving how fast you can sprint off the line.

Sight, then settle. Let the pack split before you spend energy. A frantic first 300 m is not free speed.

Leaving Hoorn · first 15 km

Get organised before the road opens.

The course carries you away from Hoorn and towards the exposed countryside. Use the change of setting to settle your breathing, get into position, and begin fuelling before speed becomes persuasive.

Start drinking before the open roads. Check effort before average speed.

The open countryside · 15–70 km

Keep power steady through the exposed middle.

From 15 to 70 km, check power and breathing after each change of direction. In a headwind, accept the lower speed rather than increasing effort to recover time. In shelter, relax your shoulders and reset your aero position while keeping your fuelling schedule.

Ride the effort, not the number. Use sheltered stretches to reset your position. If speed drops into a headwind, keep the same power ceiling.

Back to Hollandia Park · 90 km in total

Prepare for T2 on the return to Hoorn.

From 70 km, complete your planned nutrition as you return towards Hollandia Park. Let cadence rise comfortably in the closing kilometres and check that you are ready to start the run at a controlled effort.

Finish the bottle you planned. Let cadence rise before T2.

Out of T2 · first 7 km

Find your feet before the city finds your pace.

The first pass from T2 towards Hoorn will feel busier and faster than your legs really are. Use the waterfront and first aid station to turn bike legs into running legs before committing to pace.

Shorten your stride. Take the first aid station deliberately.

The historic centre and docks · 7–16 km

Make repetition work for you.

The historic centre, docks and repeated landmarks give you regular feedback. Use each pass to check posture, fuelling and effort; do not let a louder part of town become a faster kilometre by accident.

Assign a check to each landmark. Keep fuelling before you feel empty.

The final kilometres · 21.1 km

Reassess before increasing pace.

After 16 km, check whether breathing, posture and fuelling are still under control. If they are, increase pace gradually. If they are not, hold a sustainable effort through the final kilometres.

Look for three good kilometres. Keep the finish decision yours.

What to check in race week

Check the wind direction for the open countryside and the conditions in the harbour. Decide before race morning how you will ride a headwind.

Forecast statusToo early for a forecast

A race-day forecast is not meaningful yet; check back closer to the event.

Temperature
15.0–24.2°CDew point centred on 13.4°C
Wind and gusts
13.9 km/hGusts up to 42.8 km/hPrevailing direction SW
Rain likelihood
Up to 75%Wet-surface uncertainty retained

Historical baseline, 2019–2025 · Open-Meteo historical archive · Updated 2026-09-11.Historical comparison only. This is not a forecast for 2027.

Make your finish prediction and I can send this plan to you in race week.

Build the legs.
Practise the decisions.

A finish range gives you something to work towards. The preparation is specific to this race: Training has to make a steady, aerodynamic effort sustainable on open roads, the fuelling familiar and the run possible after both.

I’m Tom. With Sense Endurance Coaching, I’ll build that preparation around your life, follow how you respond and adjust the work as you get closer to Hoorn.

Explore coaching
Trisutto certified80/20 Endurance certifiedBrett Sutton’s Coach the Coach programme

Training on your own? See half distance plans

Course sourceOfficial course

PhotographyMichielverbeekCC BY-SA 4.0 · resized, cropped and monochrome; same licence