A group of bicyclists is about to attempt a ride across Iowa in 24 hours.

The Sioux City Journal reports that about 30 bicyclists will start at 4 a.m. Saturday in Sioux City. They have one day to complete the 335-mile journey to Dubuque to officially complete the Ride Across Iowa in a Day event, known as RAID.

This year marks the seventh time riders will attempt the trans-Iowa trek.

Darren Johnson, the event's organizer, is riding himself for the sixth time and has finished the full ride once, last year. Eighteen bicyclists finished the ride in 2016.

Factoring in stops, riders will have to average 14 mph for all 24 hours to reach Dubuque in time. Johnson says he doesn't recommend stopping.