Solo races: 24h, 12h and 6h
The heart of a 24-hour run is the solo 24-hour race: a single runner covers as many complete loops as possible on a measured course, until the final siren sounds after 24 hours. Alongside this, 12-hour and 6-hour solo races are well-established in the Austrian ultra scene — they appeal in particular to runners entering the format and are usually held on the same course, often with a staggered start time.
Relay races
Classic relay formats at a 24-hour run include:
- Two-person relays — two runners alternate across the full distance.
- Six-person relays — six runners, in Austrian tradition often the default relay size for a 24h event.
- Large relays of up to 12 or 24 runners — suitable for clubs, schools or companies.
Scoring usually goes by the total number of full loops the team has completed; a separate residual-distance measurement of individual members is rarely included at the relay level.
Kids' and teen relays
Specifically for younger participants, the Grimming360 in Irdning offered kids' and teen relays with a maximum of ten runners over six hours. These formats shorten the time on legs but keep the loop-course character and typically start in parallel with the main event.
Inclusion relay
A special format regularly held in Irdning was the inclusion relay: teams made up of runners with and without disabilities share the loops. It is an example of how 24-hour events function as a social bracket as much as a sporting competition.
Side events and school runs
Many Austrian 24-hour events integrate kids' and school runs into the weekend programme. They run independently of the main event, usually over much shorter distances (1–6 km), and serve as a way to develop the next generation of runners and to anchor the event locally.
From 24h to 6h: the Grimming360 example
Not every 24-hour run stays in the 24-hour format. The Grimming360 in Irdning shifted in 2019 to a six-hour main race due to falling early registrations, supplemented by cycling races and a 6-kilometre run that also counted toward the regional Bezirkslaufcup. The example shows: 24h events are logistically demanding and often face entry pressure — a reduction to 6 or 12 hours is a pragmatic option for keeping the loop-course character alive locally.
More on the course itself is on the course page; the rules around scoring are detailed under rules.