Semi du Rhône: Course, Route Profile & Map

Course & Elevation

The start is not at the finish but about 1.1 kilometres east of it on the Chemin de Cassière, just past the Chemin de Palettes junction. From there the route runs over the Route de la Croix-des-Champs and the Route des Diligences to the Bramois football ground, and from there four times round the same loop: north-west on the Route de Préjeux through the little wood by the Borgne and up onto the Rhône dyke, a kilometre and a half dead straight east along the Digue des Cavaliers, then down onto the riverbank path Rives des Martins-Pêcheurs, back onto the Chemin de Cassière and home over Croix-des-Champs and Diligences.

There is no elevation profile to manage. The loop sits between 490 and 500 metres above sea level, no section is long or steep enough to register as a climb at all, and about 55 per cent of the distance falls inside the flat gradient band. The 114 metres of climbing quoted for the full distance are the same 28 metres of valley-floor ripple counted four times. Underfoot it is asphalt on the dyke and the side roads, with made-up farm tracks in between.

All of this happens on the floor of the Valais, in the Bramois district of Sion, where the Borgne comes out of the Val d'Hérens into the Rhône. Start and finish are at the football ground, with changing rooms and a canteen in the football and tennis club buildings. The race was dreamt up in 2023 at a meeting of the Sion clubs; the first edition in 2024 drew over 300 starters, the second in February 2026 over 700. 2027 is the third running, and the Valais athletics federation has additionally awarded it the cantonal half marathon titles.

Pacing Strategy

On this course no gradient does the pacing for you. There is no hill that forces you to slow and no descent that gives anything back: from the first minute to the last, the pace is entirely your decision. The run-in and the first lap therefore almost always feel too easy, and the lap format makes it worse, because the first split arrives early and invites you to bank time.

The race is decided on laps three and four, in their eastern half. The kilometre and a half of dead straight on the Digue des Cavaliers and the riverbank path after it offer neither a change of direction nor any shelter. Run evenly to that point and you can pick up a group there; go too hard over the first two laps and you cover those same two kilometres four times, alone and progressively slower.

The trap is weather and repetition. In late February the half marathon starts at 10:30 on a valley floor that gets little sun at that time of year, and the open dyke offers no protection from the wind, while the way back has that same wind behind you. So run the second half of each lap on effort rather than on the split from the first. And use the aid station deliberately: it sits just after the lap start, so you pass it four times, but headphones are banned, and you will cover these two hours with nothing to distract you.

Training plan for Semi du Rhône: 12-week build

For a well trained age-group runner the Semi du Rhône takes roughly 1:15 to 2:00. The demand is about as uniform as a road race gets: one continuous effort just below or at threshold, with no recovery on descents and not a single change of rhythm forced on you by the course.

What decides the day is therefore not a section of the route but the ability to hold the pace you chose once the loop starts for the third and fourth time. That is trainable: long threshold blocks of two by twenty to thirty minutes, plus a long run every second week whose closing twelve to fifteen kilometres are run at target race pace. Short fast intervals alone will not give you the specific endurance the last lap asks for.

The second emphasis is running economy on hard, flat ground. Twenty kilometres of asphalt and made-up farm track without any gradient mean a very high number of near-identical strides and a corresponding sustained load on calves, Achilles tendons and shins. Put the key sessions on the road rather than on soft forest ground, add strides and targeted calf and foot strengthening, and run at least two long sessions in exactly the shoes you intend to race in.

Conditions are a training subject in their own right. A race at the end of February means building through deep winter and racing at low temperatures on a valley floor that sees little sun. Move at least one hard session a week into the late morning in the cold, test gloves, hat and the long-or-short-tights question beforehand under race effort, and allow a longer warm-up than you would need in summer. If you can, also run one hard session on a measured loop, so the monotony of the lap format is not new to you on the day.