Are strollers allowed on the course?

Yes, running strollers are welcome, but participants should be mindful of the steep hills and ensure the safety leash is attached.

Are pets allowed at the race?

No, pets are not permitted at this event.

What is included in the children's registration?

Children 14-and-under can register for a special $10 price, which includes the 5k race and entry to Biosphere 2, but does not include a souvenir shirt.

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TMC Earth Day 5K at Biosphere 2

Saturday, April 17, 2027Oracle, AZ5K

Celebrate Earth Day with a unique 5k run and walk held entirely on the grounds of the world-famous Biosphere 2. This rolling 3.1-mile course takes participants through hidden backroads, offering stunning views of the desert and the majestic Catalina Mountains. The route features mostly pavement with a brief dirt section and some challenging hills. After crossing the finish line on the beautiful Great Lawn, runners can enjoy music, food trucks, and post-race festivities. All registrants receive free entry to explore the renowned research facility, which houses diverse ecosystems like rainforests and fog deserts. It is a perfect event for both seasoned athletes and families looking for a scenic, meaningful way to support ocean reef research.