Tartan is not unlikely, since it runs near sports centre and is connected to a circular track around sports centre:
https://www.openstreetmap.org/way/193317213 - which is interestingly tagged with surface=paving_stones
Jens, is the later, circular one not tartan? It has the same red colour and is described as running track on
https://sportkoper.si/objekt/sportni-park-bonifika/
