Nocny Bieg Świętojański in Kalisz is an overnight loop race held in City Park, with the City Stadium on Wał Matejki Street functioning as the base and start-finish area. Its subtitle, “From dusk till dawn,” is literal: runners begin around sunset and continue until sunrise. Rather than aiming for a set distance, each participant runs the number of full laps they decide on or are able to complete, with completed loops determining the standings. Anyone finishing at least one lap receives a medal.
Each lap covers approximately 2 km along flat park paths near the stadium. The course is largely illuminated, although some stretches may be dimmer, and it is not PZLA-certified. A food and refreshment station is available to support runners throughout the night. The participant field is typically modest, comprising several dozen runners from Kalisz and neighboring towns, alongside club athletes from organizations like Supermaraton Kalisz and Klub Sportowy Fabryka Biegania Ostrów Wielkopolski. The distinctive aspect is the pacing: participants share the same short park loop for extended periods, with the sun dictating both the commencement and conclusion of the event.