Australian endurance athlete Phil Gore has broken the world record for the Backyard Ultra marathon event on a southern Queensland cattle farm after running more than 600 kilometres in four days.

Billed as a “race with no finish line” by organisers, the format requires runners to complete a loop of 6.7km every hour.

The race continues until only one runner remains.

The final three runners all set national records at the event.

Sam Harvey from New Zealand ran 101 loops and Harvey Lewis from the USA ran 90.

Temperatures fluctuated from -2 degrees Celsius during the night and the sunny days reached highs of 22C.

Race director Tim Walsh said the results of the event put Nanango on the running map.

“I was hoping for a course record, which was 44, and as things progressed it looked like the Australian record might eventually fall,” he said.

“It is incredible to think this race started at 7am Saturday, and went well into Wednesday.