TMC Earth Day 5K at Biosphere 2

TMC Earth Day 5K at Biosphere 2

Join us at Biosphere 2 for a 5k run and walk, entirely on the grounds of the famed facility. Whether you're a seasoned athlete or just looking for a fun way to get some exercise, you're sure to enjoy yourself at the world-famous Biosphere 2.

Date and Location

• Date: April 18, 2026
• Location: 32540 S. Biosphere Road, Oracle, AZ
• Google Maps: Click here

Event Highlights

• Course: The rolling 3.1 mile course is perfect for racing and walking, with gorgeous desert and mountain views.
• Post-Race Fun: Relax, listen to music, snag some food, and enjoy other fun activities.
• Free Entry: All registrants receive free entry to the Biosphere 2 informative tour.
• Charity: This event raises funds for the Ocean Reef research project.

Additional Features

• Souvenir Shirt: First 600 registrants will receive a shirt.
• Timed Event: Timed 5k with finisher's video.
• Awards: Age group and overall awards courtesy of The Running Shop.
• Food: Food trucks with yummy post-race food for purchase.

Schedule

Packet Pickup

• Date: Thursday, April 16
• Time: 4:00 - 6:00 pm
• Location: The Running Shop, 3055 North Campbell, Tucson
• Notes: T-shirts available on a first-come, first-served basis.

Race Day - April 18

• Registration: 7:15-8:15 am at the parking lot by the front entrance.
• Start Time: 8:30 am for TMC Earth Day 5k Run/Walk.
• Kids Dash: 9:45 am on the Great Lawn.
• Awards: 10:00 am courtesy of The Running Shop.

Important Notes

• Terrain: Mostly pavement, with a brief dirt section.
• Difficulty: Hilly in sections.
• Weather: Expected 50's - 70's.
• Pets: No pets allowed at the event.

Contact Information

• Training Advice: Contact RRCA-certified running coach Tia Accetta at tia@runtucson.net.
• Race Director: Randy Accetta, randy@runtucson.net.
• Event Partners: Run Tucson & Biosphere 2, University of Arizona.