Behobia - San Sebastián.
The Behobia - San Sebastián is Spain's biggest road race outside the marathon distance: 20 kilometres from the French border at Behobia into the heart of Donostia, with up to 30,000 starters. Two climbs define it – the long drag up Gaintxurizketa around kilometre seven and the short, steep Alto de Miracruz shortly before the finish. Misjudge either and the closing kilometres become pure survival.
Behobia - San Sebastián 2026: Course, Elevation & Route Profile
The start sits at sea level on the Bidasoa in Behobia, the border village beside Irun. The road kicks up briefly after barely a kilometre, and from there the course follows the old corridor west through the valleys. At kilometre 6.6 the Gaintxurizketa begins: 800 metres averaging 6.6 per cent with ramps to eleven, the longest sustained climb of the day. Over the top it rolls downhill and undulating through Errenteria and past the harbour inlet at Pasaia.
The second test comes late. At kilometre 16.2 the Alto de Miracruz arrives, only 350 metres long but averaging 7.1 per cent and touching 12.7 – on tired legs, at exactly the point where a race begun too fast comes apart. Then the Avenida de Ategorrieta drops into the city, and the last kilometre and a half runs flat to the finish on the Alameda del Boulevard beside the old town.
This is not a picture-postcard route. It runs through border traffic, industrial valleys and the working port of Pasaia before Donostia finally opens out in all its elegance at the end, and that contrast is much of its reputation. The race was first run on 30 March 1919 and has been a mass event since 1979; today a November Sunday fills it with 30,000 people, and the recovery area on Plaza Okendo is closer to a street party than a finish enclosure. The official cut-off is 2:35.
| Start | Length | Ø | Max. | Gain | Cat. |
|---|---|---|---|---|---|
| km 1 | 0.7 km | 3.2 % | 4.9 % | +22 m | — |
| km 6.6 | 0.8 km | 6.6 % | 11.1 % | +53 m | — |
| km 16.2 | 0.4 km | 7.1 % | 12.7 % | +25 m | — |
Climb categories follow the road-cycling convention and rate the terrain itself (length and gradient) regardless of sport: Cat. 4 marks the easiest rated climbs, Cat. 1 the hardest, and HC (hors catégorie, “beyond categorization”) is reserved for the most brutal ascents. Short climbs below the Cat. 4 threshold stay unrated.
How to pace Behobia - San Sebastián.
Start under control
Split this race into two halves with different rules. Up to kilometre seven, deliberately hold back. The start is at sea level, the opening kilometres are fast and the field is enormous – the classic error is riding the gradient and the pull of 30,000 people and arriving at the foot of Gaintxurizketa already in the red.
Hold your rhythm
Run Gaintxurizketa by effort, not by split; 800 metres at over six per cent will cost you time, and that is fine. The payback comes afterwards: the long rolling descent toward Errenteria and Pasaia can be run very economically if your quads are still fresh. Overcook the climb and you lose twice on exactly that stretch.
Spend what is left
The race is decided at the Alto de Miracruz at kilometre 16.2. It is short, but at up to 12.7 per cent it is steep enough to expose whatever you have left after 16 kilometres. Plan it as its own effort and ease off for roughly half a kilometre before it. And do not attack the Ategorrieta descent that follows – you still need your legs for the flat final kilometre to the Boulevard.
Training plan for Behobia - San Sebastián: 12-week build
Build the base
As an age-group runner, expect roughly 1:20 to 2:20 for the 20 kilometres; the cut-off is 2:35 from your start. The effort is largely aerobic but not uniform: about a quarter of the course climbs, almost 30 per cent descends, and only 44 per cent sits in the flat band. Across 196 metres of gain and a similar loss, that means constant changes of rhythm rather than one held pace.
Train race pace
The first training priority is climbing strength endurance. Prepare for Gaintxurizketa with six-to-ten-minute climbs at five to seven per cent run at threshold, and for Miracruz with short, steep 60-to-90-second repeats on a double-digit gradient. The order matters most: put those short steep efforts at the end of a long run, so your body learns to handle them with 16 kilometres already in the legs.
Rehearse the course
Second, train the downhills. A long stretch after Gaintxurizketa runs downhill, and Ategorrieta drops sharply again just before the finish. Build brisk descending segments into your long runs to condition your quads for the eccentric load – this is what decides whether you can still run the flat final kilometre or merely survive it.
Arrive fresh
Finally, rehearse the logistics. The foot race does not set off until 10:00, and with 30,000 starters you will spend a long time in the start area beforehand: practise the late breakfast and the wait on your longest training day. Early November on the Basque coast also means changeable, damp weather – test your kit and your shoes on wet tarmac before you race in them.
Courses
Download the Behobia - San Sebastián course as a GPX file for your watch or bike computer.
Let YOUB adapt your plan for Behobia - San Sebastián dynamically
Ben connects your goal, the course, current load, recovery, and calendar. Your plan stays pointed at race day even when real life is not perfectly plannable.
Everything about Behobia - San Sebastián.
How long is Behobia - San Sebastián?
Behobia - San Sebastián is 20 km long. That distance shapes how much aerobic endurance, pace durability, and race-specific work belong in the training plan.
How much elevation gain does Behobia - San Sebastián have?
Behobia - San Sebastián has around 192 m of elevation gain over 20 km. That affects pacing, muscular load, and preparation for late-race sections.
What is the route profile of Behobia - San Sebastián?
Behobia - San Sebastián is classified as Rolling, averaging 9.7 vertical metres per kilometre. 44% of the route is flat, 24% climbs moderately (2 to 6%) and 2% is steeper than 6%.
What climbs does Behobia - San Sebastián have?
The hardest climb of Behobia - San Sebastián starts at kilometre 6.6, runs for 0.8 km at an average of 6.6% and gains 53 metres. 3 climbs are mapped in total.
Is Behobia - San Sebastián a loop course?
No, Behobia - San Sebastián is a point-to-point course: start and finish are in different places.
Is there a GPX file for the Behobia - San Sebastián course?
Yes. The Behobia - San Sebastián course is on this page as a free GPX download — ready to import into Garmin, Wahoo, Komoot, Strava or any other app that reads GPX.
How should I prepare for Behobia - San Sebastián?
Preparation for Behobia - San Sebastián should account for 20 km, 192 m of elevation gain, current training load, and available training time. An adaptive plan helps place key sessions without ignoring recovery and real life.
What pacing strategy works for Behobia - San Sebastián?
The pacing strategy for Behobia - San Sebastián should reflect 20 km, 192 m of elevation gain, and your current fitness. Start controlled and keep margin for sections where the profile or fatigue makes target pace harder.
When does Behobia - San Sebastián take place?
Behobia - San Sebastián takes place on November 8, 2026.
Where does Behobia - San Sebastián take place?
Behobia - San Sebastián takes place in Irun, Spain.
How do I register for Behobia - San Sebastián?
Registration runs through the organiser: behobia-sansebastian.com. YOUB shows you the course, elevation profile and training plan for your preparation.
