pacertrip.

PACERTRIP CITY EDITIONFR / RACE GUIDE

Trail Les 40 Bosses

The city you want to run becomes your next trip.

FRDec 5, 2026120km · 75km · 45km +2 more events

YouTube · Run Addictive

Race date in 57 days: Dec 5, 2026 Sat
City · Distance: Saint-Leu-la-Forêt · 120km · 75km · 45km +2 more events
Entry fee: €20From the 2025 edition
Status: OpenFri, March 20, 2026 ~ TBDSee how to enter ↗

Official website ↗

Instagram

D-day as of Oct 9, 2026

About the race Runner stories How to enter Course Race Prep Travel

Why you dream of this race

THE DREAM

ABOUT THE RACE

A day you'll remember,
long past the finish line.

This is the 6th trail competition held in the Montmorency Forest, France.

The road to your own record

Picture the course in advance
and find the pace that fits you.

When the city cheers

Streets lined with cheers, runners all around.
You'll be part of that scene.

The trip that follows the run

Take it slow with the finish still in you,
and meet the city all over again.

Stories from those who ran it first.

From the joy of finishing to the tough moments — read what runners wrote themselves.

Race reports: 2

Olivier ChavasseauRan in 2022 · Finish time 6:15

“I kept moving up the field while holding the same rhythm.”

The runner ran with a sibling at Trail des Quarante Bosses, then accelerated after halfway to pass about 180 people. Finishing the unexpectedly long course in 6 hours 15 minutes, they appreciated improved fitness and careful course marking.

Quoted from the original · translated

Original quote

Je continue sur le même rythme et gagne encore des places.

Read the original on Christian Baigue : De L'Athlé au Trail

ShotoRan in 2021 · Finish time 6:24

“Today I decided not to neglect the aid stations.”

The runner fell several times on muddy, slippery woodland trails at Trail des Quarante Bosses. A fast opening pace and running short of water later made it tough, but they finished in 6 hours 24 minutes, acutely aware of hydration's importance.

Quoted from the original · translated

Original quote

J’ai décidé aujourd’hui de ne pas négliger les ravitos.

Read the original on Kikourou

We translated a short line from each public race report and summarized the experience. Finish times are as stated by the author, and past editions may differ from this year's weather and operations.

See it on video,
feel it through their stories.

Preview the course and read what runners who went before you wrote.

🏃🏻‍♂️Trail les 40 bosses 2021 [by RUN ADDICTIVE] reportage 🎬 inside HD1080p 🎥

Run Addictive

View on YouTube

This may be from a past edition. Check the organizer for this year's course and operations.

The way in that fits you

YOUR ENTRY

How to reach the start line —
start with what fits you.

Here are the ways to enter and what each requires.
Check the organizer's page for whether entries are open.

From the 2025 edition

10K

Entry cost €20

subject to change — verify officially

Organizer's page

Official race website Entry options

From the start line to the finish

RACE WEEK

The 120km I'll run

Know the course and time limit, and race day comes into focus.

From the 2025 edition

Runners start · local timeFrom 16:30

Time limit24 hours

120 km: 24 hours (1st loop 14 hours 30 minutes + 2nd loop 9 hours 30 minutes) · 75 km: 16 hours · 45 km: 8 hours · 20 km: 4 hours · 10 km: 2 hours 30 minutes — as of 2026

€20–€110
Registration and PPS fees extra — 10 km €20 · 20 km €30 · 45 km €50 · 75 km €80 · 120 km €110

City center · not the start line

We have not confirmed the start line coordinates yet. The map shows the host city.

START

Saint-Leu-la-Forée city center

FINISH

Rue des Ecoles, Saint-Leu-la-Forêt

Cut-off
120 km: 30 km Taverny, Sat. 10:15 p.m. · 53 km Chauvry, Sun. 2:30 a.m. · 59 km Route du Faîte 3:45 a.m. · 75 km Saint-Leu gym 7 a.m. · 93 km junction 11:20 a.m. · 95 km Taverny 11:30 a.m. · 107 km Chauvry 2 p.m. · finish 4:30 p.m. / 75 km: 30 km Sat. 10:30 p.m. · 53 km Sun. 2:30 a.m. · 59 km 3:45 a.m. · finish 8 a.m. / 45 km: 19 km junction 11:20 a.m. · 20 km Taverny 11:30 a.m. · 33 km Chauvry 2 p.m. · finish 4:30 p.m. / 20 km: 13 km 12:10 p.m. · finish 2 p.m. / 10 km: finish 4:30 p.m. — as of 2026; miss a cut-off point and your bib and chip are taken

Events are the Trail 120 km and Trail 75 km, starting at 4:30 p.m. local time.

The course has 4,900 meters of elevation gain.

As of 2026, the event runs over two days: the 120 km and 75 km start at 4:30 p.m. on Saturday,

December 5, and the 45 km (8:30 a.m.), 20 km (10 a.m.), and 10 km (2 p.m.) on Sunday, December 6.

All races start on Rue du Général Leclerc in front of Saint-Leu-la-Forêt town hall and finish on Rue des Ecoles.

The 120 km is a course of one 75 km loop plus one 45 km loop.

The time limit is 24 hours for the 120 km, 16 hours for the 75 km, 8 hours for the 45 km, 4 hours for the 20 km, and 2 hours 30 minutes for the 10 km;

miss a cut-off point time and your bib and chip are taken.

Poles are allowed from the 5 km mark in the 120, 75, and 45 km, and banned in the 10 and 20 km.

Running with an unregistered pacer means disqualification.

Elevation gain: 4900 m
Typical race-season temperature: around 4°C (38°F): Long sleeves + a throwaway layer for the start

Participant benefits

Water stations

120Kms · 75Kms · 45Kms · 20Kms

Aid stations

120Kms · 75Kms · 45Kms · 20Kms

To the start line,
step by step.

Pick up your bib, check your wave.
So on race morning, you can just run.

From the 2025 edition

Pick up your bib at the expo

Bib pickup for all distances is on Saturday, November 28, 2026, 10 a.m.–6 p.m.
at the Gymnase « Les Dourdains » on Place Foch in Saint-Leu-la-Forêt.
On Sunday, December 6, pickup at the same gym is 7–7:30 a.m.
for the 45 km, 7–9 a.m.
for the 20 km, and 11 a.m.–1 p.m.
for the 10 km.
As of 2026 — Saturday, November 28, 10 a.m.–6 p.m. at Décathlon d'Herblay (all distances) · Saturday, December 5, 10 a.m.–7 p.m. at the Gymnase « Les Dourdains » (all distances) · Sunday, December 6, same gym: 45 km 7–7:30 a.m., 20 km 7–9 a.m., 10 km 11 a.m.–1 p.m.

Décathlon d’Herblay · Gymnase « Les Dourdains », Place Foch, Saint-Leu-la-Forêt

Google Maps

and on Saturday

Stations & transport near the venue

Getting to the startGare de Saint-Leu-la-Forêt (Transilien Line H, direction Persan-Beaumont, from Paris-Nord)
Getting to the finishGare de Saint-Leu-la-Forêt

Source · checked Aug 22, 2026

More details

Getting to the start

Gare de Saint-Leu-la-Forêt (Transilien Line H, direction Persan-Beaumont, from Paris-Nord)

Start is at the Gymnase des Dourdains, a short walk from Gare de Saint-Leu-la-Forêt; about 30 minutes by train from Paris Gare du Nord. Good public transit access via RER/Transilien; multiple race distances held Dec 5-6, 2026.

Map

Getting to the finish

Gare de Saint-Leu-la-Forêt

Finish is in the same area near the Gymnase des Dourdains / forest of Montmorency, walkable back to the station.

Map

Start shuttle

No organizer shuttle bus mentioned; public transit (Transilien Line H) is recommended over driving.

Source · checked Aug 22, 2026

READY TO RUN

From race morning to after the finish.

Your start time, fuel and bag drop.
Know them ahead and the run feels easier.

A winter trail race up and down the Montmorency Forest. Check entry, cut-off point times, and mandatory gear first.

Managing your entry and the waiting list

Registration for 2026 opened online at noon on March 20, and sold-out races use a waiting list.

If someone cancels, an invitation email goes automatically to the first person on the waiting list.
Bib resale is banned, and any bib obtained through unofficial channels is canceled.
The GPX file for the course is released on December 2, three days before the race.

Getting to Saint-Leu-la-Forêt by train

Take Transilien Line H toward Persan Beaumont and get off at Saint-Leu-la-Forêt station.

Parking is very tight, so public transit or carpooling is recommended.
Pick up your bib with ID; a proxy needs a copy of the runner's ID and a letter of authorization.
Bring your own safety pins.

Bring your own cup to cover the gaps between aid stations

There are no cups at the aid stations, so bringing your own cup is essential. On the 75 km and 120 km courses, the distance between aid stations can be nearly 20 km (as of 2026).

Race	Aid station
10km	Course aid: none
20km	13km (Barrière Bas Corbon)
45km	13km · 20km · 33km
75km	22 km (Étang Marie) · 30 km (Taverny, hot food) · 53 km · 59 km
120km	75 km course aid, plus 75 km (Saint-Leu gym, hot food) · 95 km (Taverny, hot food) · 107 km

Everyone gets beer and a hot dog at the finish.

Bring all the mandatory equipment

Missing any mandatory gear means immediate disqualification, and there are spot checks on the course.

Race	Mandatory equipment
75·120km	Headlamp and spare batteries, a waterproof jacket with a hood (10,000 or higher), an emergency blanket, water and food, a cup, a fully charged phone, and a neck warmer
45km	A waterproof jacket with a hood, an emergency blanket, a cup, a fully charged phone, and a neck warmer
20km	Cup

Ranked runners must have a GPS watch, and their times will be checked at the finish.
Littering on the course means immediate disqualification.

Bag storage and drop bags

Bag storage is available at the gym at the start and finish.

75 km and 120 km runners can leave a drop bag for the Taverny aid station (30 km and 95 km); hand it in at the Saint-Leu drop-off before 3 p.m. on December 5.

Check the weather warnings

The race is canceled if France issues a level 3 (orange) or level 4 (red) weather warning.

Times are local to Saint-Leu-la-Forêt. Check the latest official information before the race.

A trip built around the race

STAY A LITTLE

MAKE IT A RUNTRIP

The race is one day,
the trip can be longer.

From a hotel that makes race morning easy,
to the meals and views you'll enjoy with the medal on.

Kyriad Sannois - Ermont

Hotel · 4.3km

8.2/10(650)

View on Booking.com

Paris Moulin Rouge Show & Seine River Cruise Ticket

€207

Trail Les 40 Bosses

About Trail Les 40 Bosses — what makes it special

A day you'll remember,long past the finish line.

The road to your own record

When the city cheers

The trip that follows the run

Trail Les 40 Bosses runner reviews and race reports

Stories from those who ran it first.

See it on video,feel it through their stories.

🏃🏻‍♂️Trail les 40 bosses 2021 [by RUN ADDICTIVE] reportage 🎬 inside HD1080p 🎥

How to enter Trail Les 40 Bosses — registration routes

How to reach the start line —start with what fits you.

10K

Trail Les 40 Bosses course map and elevation

The 120km I'll run

Saint-Leu-la-Forée city center

Rue des Ecoles, Saint-Leu-la-Forêt

Participant benefits

Water stations

Aid stations

Where and when to collect your Trail Les 40 Bosses race bib

To the start line,step by step.

Pick up your bib at the expo

Décathlon d’Herblay · Gymnase « Les Dourdains », Place Foch, Saint-Leu-la-Forêt

Stations & transport near the venue

Getting to the start

Getting to the finish

Start shuttle

From race morning to after the finish.

Managing your entry and the waiting list

Getting to Saint-Leu-la-Forêt by train

Bring your own cup to cover the gaps between aid stations

Bring all the mandatory equipment

Bag storage and drop bags

Check the weather warnings

The race is one day,the trip can be longer.

Kyriad Sannois - Ermont

Paris Moulin Rouge Show & Seine River Cruise Ticket

Paris Macaron & French Dessert Cooking Class

Stade de France: Behind The Scenes Tour

Campanile Taverny

Paris Museum Pass & 24-Hour City Tour Bus & Optional Seine River Cruise

Paris Montmartre Food Tour (Including Wine Tasting)

Hotels near the Trail Les 40 Bosses start line in Saint-Leu-la-Forêt

Hotels that make race morning easy

Kyriad Sannois - Ermont

Campanile Taverny

Logement moderne, dans mon jardin, près de Paris et stade de France avec place de stationnement

La Villa Perchée 4 Appartements Élégants, indépendants, sauna Privé, sport, terrasses et Vue Panoramique, Parking, 20 min STADE DE FRANCE

Superbe appartement avec vue sur la tour Eiffel

La Clairière De La Reine Hortense - Pierres D'histoire

appartement type f2 proche PARIS 25 KM

Time for you, before and after the finish

Paris Moulin Rouge Show & Seine River Cruise Ticket

Paris Museum Pass & 24-Hour City Tour Bus & Optional Seine River Cruise

Paris Gare du Nord Luggage Storage Service

Paris Gare de l'Est Luggage Storage Service

Paris to Versailles City Transfer Service

Frankfurt–Paris DB/Deutsche Bahn Train Ticket

London–Paris Eurostar Train Ticket

Brussels–Paris SNCF Train Ticket

Paris Notre-Dame Luggage Storage Service

Basilica of Saint Denis Tickets

Saint-Denis Basilica Cathedral Ticket in Paris

Paris Jardin d’Acclimatation Admission & 8-Attraction Ticket

Paris City Highlights & Palais Garnier Small-Group Tour

Montmartre Museum Admission Ticket

Paris Salvador Dalí Exhibition Ticket

Paris Moulin Rouge Show Ticket

Hiking Adventure in Van Gogh’s Footsteps (6-Mile Walk)

3-Hour Bike Tour of Paris's Main Attractions

Paris E-Bike Tour (Day/Night Options Available)

Eiffel Tower Half-Day Guided Climbing Tour

Paris Hidden Gems 180-Minute Bike Tour

Paris Private E-Bike Tour

Pont Alexandre III Half-Day Guided & Bike Tour

[Korean Support] From Paris · 6-Night, 7-Day European Shuttle to Southern France & Spain with Free Exploration (April–October)

Paris Eiffel Tower & Arc de Triomphe Half-Day Small-Group ATV Tour

La Vallée Village Shopping Tour Shuttle Service (Departing from Paris)

Paris City Lights Tour & Moulin Rouge Show (Champagne Included)

A day you'll remember,
long past the finish line.

See it on video,
feel it through their stories.

How to reach the start line —
start with what fits you.

To the start line,
step by step.

The race is one day,
the trip can be longer.

Trip prep too,
light and in one place.

With runners who dream of
the same start line.