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Posted on: August 22, 2023

Tres Hermanos Conservation Authority Tours of the Ranch Sept. 23 - Registration Closed

Tres Hermanos Ranch

Update: All spots have been filled, registration is CLOSED. Registration confirmation emails will be sent the week of September 11, 2023.


On Saturday, September 23, the Tres Hermanos Conservation Authority is inviting the community to join in a free guided tour of the southern portion of the Tres Hermanos Ranch (Ranch).

The 90-minute tours of the property begin at 9 a.m. and will depart from the Diamond Bar Center every hour, until noon. Participants will travel to the Ranch via shuttle bus accompanied by a guide who will provide details about the history of the property, from its origins to present-day operations. The tour will be highlighted with three stops along the route where participants will disembark the shuttle to hear from a local expert about the Arnold Reservoir, property use through its history, and local flora and fauna that call the Ranch home.

This event takes place on a working ranch in a natural and unimproved setting. Participants may be exposed to a variety of wildlife including insects, vectors, snakes, coyotes, rodents, livestock, vegetation, and other natural elements. The tour requires a moderate amount of walking on uneven terrain and unpaved surfaces; therefore, ADA accommodations cannot be made for this activity.

Advanced online registration is required and will be accepted on a first-come, first-served basis. In the event of cancellations, spots will be filled via a waitlist. Early registration is suggested as space is very limited due to the nature of the activity. 

Registration opens at 9 a.m. on Tuesday, September 5, 2023, via the Tres Hermanos Conservation Authority website at

About Tres Hermanos Conservation Authority
Formed in February 2019, the Tres Hermanos Conservation Authority is a joint powers agency with representatives from the cities of Chino Hills, Diamond Bar, and Industry. Its purpose is to work collaboratively to coordinate the ownership, maintenance, and use of the of the 2,445-acre Tres Hermanos Ranch property.

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