Bieg Murowaniec - Tu się Biega is a local running event held at the beach by Zalew Murowaniec in the Koźminek commune. Participants can select a shorter route of approximately 5.5 km or a main route of 11 km, suitable for less experienced runners and those seeking a challenging local competition. The event has a participant limit; one edition saw 171 runners.
The course circles the reservoir, using the beach as the event hub with the water as a backdrop. It attracts runners from various towns, alongside local sports enthusiasts and community leaders. The Municipal Office of Koźminek Commune is the organizer, with the mayor of Koźminek serving as host. The event is also part of the Biegowe Grand Prix Ziemi Kaliskiej, integrating it into a broader regional running series.