Semi-Marathon de Cardiff 2026

Cardiff Castle, the Millennium Stadium, and the sweep of Cardiff Bay provide this road race with a significant event atmosphere while retaining the core objective: run hard through familiar streets. The Semi-Marathon de Cardiff is a fixture in the SuperHalfs circuit. Its 23rd edition ranks among the larger European half-marathon events, attracting tens of thousands to the start line. The course offers an engaging tour through the city’s key landmarks, including the Principality Stadium, Civic Centre, the bay, and the castle. It is characterized by flat and gently rolling terrain, suitable for runners of all abilities to find their pace or aim for a personal best. Numerous spectators and race-day activities contribute to a lively, rather than subdued, atmosphere.