Os 21 do Camiño is a half marathon held in June in Galicia. It begins in Palas de Rei, Lugo, and concludes in Melide. The primary race covers 21 km, with a 6 km alternative for participants seeking a shorter distance within the same event. Asociación Deportiva Cerne is the organizer, and registration typically closes very quickly.
The course crosses stage 29 of the Camino de Santiago, connecting Palas de Rei and Melide. This section is known for its pilgrimage route. The terrain alternates between dirt and asphalt, and the ascents contribute to a challenging profile compared to a flat road race. Over a thousand participants have competed in a recent year, and Galician bagpipes are played by folk groups along the route, adding a local musical element to the Camino setting.