About this race
Berjatrail Siporex 2026 – Semi-Night Trail Running in Bourgoin-Jallieu, Isère
Looking for a trail race in Bourgoin-Jallieu, a night trail in Isère or a great event to prepare for the SaintéLyon? The Berjatrail Siporex returns on Saturday, 7 November 2026 for its 6th edition.
Organised by CSBJ Athlétisme, the Berjatrail is a semi-night trail running event starting from the Antonin-Berliat Stadium in Bourgoin-Jallieu, in northern Isère, between Lyon, Grenoble and Chambéry. As daylight fades, hundreds of headlamps light up the trails, woodland and hills surrounding the town, creating a unique transition from daytime running to night trail conditions.
A fast-growing trail event in Isère
The Berjatrail has grown strongly in recent years: 350 participants in 2023, 500 in 2024 and 850 in 2025. Registrations were closed early in 2025 to preserve safety, fluidity and the quality of the participant experience.
In 2026, the organisation is preparing to welcome up to 1,000 runners and walkers.
Three trail races and one Nordic Walking event
The Berjatrail Siporex 2026 offers four formats for different levels and goals:
9 km Foraspi – 150 m D+: an accessible and dynamic course, ideal for discovering trail running or enjoying a short, fast challenge.
16 km Distance+ – 300 m D+: a balanced route combining endurance, hills and trail terrain.
24 km Buff – 480 m D+: the longest and most demanding race, designed for experienced runners and end-of-season preparation.
9 km GBL Détection Nordic Walking: a different way to enjoy the Berjatrail atmosphere and the trails around Bourgoin-Jallieu.
The first starts take place from 4:45 pm, allowing participants to experience the transition from daylight to darkness during the race.
An ideal race to prepare for the SaintéLyon
Held only a few weeks before the SaintéLyon, the Berjatrail is an excellent preparation race for runners targeting a longer night trail.
It offers real conditions to test headlamps, trail shoes, clothing, nutrition, hydration, pacing and race management in autumn conditions.
A friendly, community-driven trail
The Berjatrail is more than a race. Nearly 100 volunteers are involved in course marking, aid stations, road crossings, bib collection, logistics, safety and the finish area.
Their energy gives the event its welcoming, authentic and friendly atmosphere.
At the finish, runners and walkers return to the Berjatrail village to meet other participants, volunteers and partners, enjoy refreshments and extend the evening together. A hot meal and drink can also be booked as an optional extra when registering.
The event also continues its efforts to reduce waste, particularly through bulk products at aid stations and measures designed to limit unnecessary packaging.
Whether you are looking for a trail race near Lyon, a trail in Isère, a semi-night race in Bourgoin-Jallieu, a first night trail experience or a preparation race for the SaintéLyon, the Berjatrail Siporex 2026 offers a challenge for you.
Saturday, 7 November 2026
Antonin-Berliat Stadium – Bourgoin-Jallieu, Isère, France
9 km • 16 km • 24 km trail races • 9 km Nordic Walking
Registrations open.