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Introduction

Everything You Wanted to Know About The NASA 25 Hour

The NASA 25 Hours of Thunderhill is the longest closed-course endurance race in North America. Begun in 1998 as the Timex 12 Hours of Thunderhill, the race expanded to 25 hours in 2003, and has since evolved to become known as one of the most grueling endurance races in the nation, attracting amateur and professional sports car drivers from around the world.

Ozarks International Raceway in Gravois Mills, Mo., will be the site of the event this year, which will take place November 13-16, 2025.

FAQ

Questions and Answers to Feed Your Curiosity

The 25 Hours of Thunderhill was held at Thunderhill Raceway Park in Willows, Calif., from 1998 through 2023. Beginning in 2025, the race will take place at Ozarks International Raceway. 

If there are no weather delays, the race begins at 11 a.m. Saturday and ends at noon Sunday

No. A minimum of two drivers are required.

Most teams have settled on a range of three to six drivers to run the event.

Yes, but rookies may only drive during daylight hours, so if you want to run the whole race, you must have drivers with regular competition licenses to handle night duties.

Yes. The NASA 25 Hour requires a team effort, and that means a full crew, professional or volunteer. You’re going to need people to do everything from fueling, servicing and repairing the car to forming race strategy and keeping everyone rested and fed.

Everything from the Mazda Miata and BMW 3-series cars compete alongside quarter-million-dollar prototypes. You can run what you brung or bring as much car as you want. There is a class for every vehicle except for open-wheel cars.

Go to the NASA Events page and get signed up when registration opens midsummer and before it closes in late November.

News

Latest NASA 25 Hour News

Videos

NASA 25 Hour Videos

Contact Us

NASA 25 Hour Contacts

25 Hours of Thunderhill
Donna Lane
Region: MidAmerica
Title(s): Regional Director
Series: 25 Hours of Thunderhill
Email