The Zimowy Półmaraton Jaskiniowego Niedźwiedzia is a winter mountain race in Kletno, Poland, featuring a main event of approximately 20 kilometers. The name translates to Winter Half Marathon of the Cave Bear. The elevation gain of about 1,050 meters over the course indicates it is a challenging mountain run rather than a flat road half marathon.
The route is designated RMT2, with G5 terrain and an average gradient of 5%. This suggests consistent climbing on difficult ground, prioritizing endurance over pure speed. One past edition saw 99 finishers in the main race. The men’s winner completed the course in just over two hours, and the women’s winner finished in 2:26, illustrating the course's difficulty.