Bad Ass Backyard Ultra - Rio Linda, CA

The Bad Ass Backyard Ultra (B.A.B.U.) is an endurance running event held at Dry Creek Parkway in Rio Linda, California, near northern Sacramento. This backyard ultra challenges runners to complete a 4.16-mile loop every hour, starting on the hour, with each loop called a "yard." Participants must be ready to start each new loop on time or face elimination. The last runner to complete the most loops wins.

Originating in 2023 as a fatass event, B.A.B.U. became an official backyard ultra in 2024 through collaboration between Skybreaker Racing and Auburn Area Trail Runners and is now part of Singletrack Running. It is affiliated with the national and world backyard ultra championships. Visit the organization's website for the most recent information.