On May 17, 2026 the Basque Country in northern Spain will host the 25th Zegama-Aizkorri Mountain Marathon, which starts at 09:00 local time (15:00 Beijing time). The full marathon covers 42 km, crosses the four highest peaks of the Basque region and features 2,736 m of cumulative ascent. As the opening race of the 2026 Golden Trail World Series (GTWS), it has attracted many of the world’s top trail runners — including Kilian Jornet, orienteering queen Tove Alexandersson, and China’s Shen Jiasheng and Shi Guo — setting the stage for an epic showdown. Men’s elites: Shen Jiasheng, racing for Salomon on home turf, arrives a week after competing at Transvulcania on May 9 and will take on another high-intensity trail race; Nnormal’s China-signed elite Shi Guo makes his international debut — we’ll be watching for strong performances from both. Trail-running legend Kilian Jornet returns to his home course for the 25th edition. Holder of the men’s course record 3:36:40 (2022), can he stage a triumphant return on this most familiar route? Also from Nnormal, defending champion Elhousine Elazzaoui faces even stronger opposition this year — can he handle the pressure? Swiss “hill king” Rémi Bonnet, a core member of Salomon, is also a force to be reckoned with, but after a subpar outing at the Grand Raid Ventoux 50k in late April 2026, can he regain form at Zegama? 2023 champion Manuel Merillas, who already won two skyraces earlier in 2026, is among the most serious contenders for the title. Women’s elites: Tove Alexandersson, currently No. 1 in the women’s ITRA performance ranking and widely regarded as the greatest orienteer of all time, arrives at Zegama for her debut as a formidable challenger — many see her as the strongest threat for the title and even capable of challenging the women’s course record of 4:16:43 set by Nienke Brinkman in 2022. Defending champion Sara Alonso, Judith Wyder and Malen Osa — last year’s top three — will race together again, making for an exciting field. Long-distance specialist Anna Tarasova — can she translate her endurance into this intense, shorter-format race? In addition, the 2026 GTWS has introduced a team competition and extra segment bonus prizes. This Sunday’s Zegama opener will ring in a new era for trail running. Who do you back to win? Which brand will come out on top? Tune in to the Trail Running Big Bang live stream and let’s find out together! #ShenJiasheng#Salomon#KilianJornet#2026GoldenTrailWorldSeries#Zegama