How long can you last? In this last-one-standing race, runners complete a 6-mile loop every 90 minutes. Miss the cutoff and you are out. Anyone who finishes all 17 loops earns a belt buckle for a 102-mile achievement.

The race starts at 3 PM Friday at Crosby Family Confluence Park and continues overnight into Saturday. There are 2-person and 4-person relay divisions and a kids division too. Registration is at ultrasignup.com.