The Loiu 500 Trail is a short mountain-running event held in Loiu, a town in Bizkaia within Spain’s Basque Country. The primary race covers 12 km, and the event also features the Martxa Txiki, a 1.8 km option for a significantly shorter run. This event occupies a niche in mountain sports, bridging trail running, mountain racing, and hiking, presenting itself more as a local off-road competition than a large urban road race.
The Loiu town council organizes the event, supported by local businesses. This is its second edition, as indicated by the source. Participants can collect bibs, shirts, and timing chips at Decathlon Bilbao. Loiu residents also have a local pickup option at the municipal library. The reasonable entry fees and the short Martxa Txiki contribute to a community-focused atmosphere, welcoming both experienced trail runners and those seeking a less demanding way to participate in the day's activities.