Oskarshamn Backyard 6h is a six-hour backyard race held at Havslätt Motionsområde in Oskarshamn. Runners begin together in the morning and depart again on the hour for each subsequent lap. The race consists of five laps of 6.7 km, concluding with a longer final lap that completes the marathon distance of 42.195 km. Participation is flexible; runners can choose to run every lap to achieve the full marathon or complete only a portion of the day's event.
The course largely utilizes the local exercise trail at Havslätt, featuring moderate ascents instead of a flat road-race profile. A horn signals three, two, and one minute prior to each new lap's start, and bibs must be displayed at the front for lap verification. The first runner to finish the final lap is the winner. Additionally, the event includes prize drawings for all participants, medals for those completing at least one lap, a Tire Prize on lap three, a 670 m children's race for ages 3-12, and the option to purchase sausages and coffee on-site.