Irvine Ranch Open Space

Irvine Ranch Open Space 

Eastern Foothills of Orange County. Access through scheduled events only.

Phone: 714-973-6696


Acres: 22,500

Printable Map

Park Hours: Access only through scheduled programs or Wilderness Access Days.

Black Star Canyon Road is always open for public use and access to Cleveland National Forest.

Parking: Free

Dogs: Not permitted, except on Black Star Canyon Road.

Activities and Programs

The Irvine Ranch Open Space consists of protected wildlands, including six nature preserves. OC Parks stewards these special lands in close coordination with the Irvine Ranch Conservancy as land management contractor and The Nature Conservancy, a conservation organization. Various educational and recreational opportunities are available through regularly scheduled programs. Other uses are prohibited as specified by deed restrictions and conservation easements. We invite you to visit and select from the many free activities offered.

Trails: hiking, biking and equestrian activities through regularly scheduled programs

Monthly self-guided Wilderness Access Days scheduled

Named a State and a National Natural Landmark

Volunteer opportunities


On June 29, 2010, the Orange County Board of Supervisors voted to accept a donation of 20,000 acres from the Irvine Company to the County for preservation and guided recreation. Additional acreage was donated in late 2014. The historic Irvine Ranch’s origins date back to the 1830s as a Mexican Land Grant to Don Jose Andres Sepulveda. In 1876, James Irvine bought out his partners on the land. During this time, he successfully fought to secure the borders from squatters and the Southern Pacific Railroad. From 1876 to 2010, the historic Irvine Ranch was used for ranching and mining operations, and evidence of this can still be observed. Based on evaluations and the recommendations of the Science Advisory Committee of the National Park Service, the National Park Service Advisory Board, and the National Park Service director, the Secretary of the Interior designated the Irvine Ranch National Natural Landmark in 2006. A similar objective review led to the designation as a California Natural Landmark on Earth Day 2008 by the California State Parks director.


October 31, 2018 
Black Star Canyon Road Restricted Parking Zones

News ImageThe County Board of Supervisors approved the following two recommendations - 1. No Parking Zone / Tow Away Zone near the Black Star Canyon Access Gate and 2. No Parking Zone along Black Star Canyon Road between 10 pm - 4pm. See PDF for more information.

March 19, 2019 
2019 Wildflower Season

Wildflowers are now blooming in OC Parks. Please follow all park rules while you enjoy the flowers. Make sure to stay on marked trails and do not pick the flowers. Click the link for a video about wildflower viewing.

September 21, 2018 
Electric Bicycles Now Permitted on Regional Bikeways

For the past 20 years, Orange County Codified Ordinance OCCO 2-5-29(n) prohibited the use of all motorized conveyances, including electric bicycles (eBikes) on all County bikeways and trails.

On July 17, 2018, the Board of Supervisors passed a revision to the ordinance, making the following exception: “Class 1 and Class 2 electric bicycles, as defined by the California Vehicle Code, on those regional paved, off-road bikeways designated for such use by the Director of OC Parks.”

Currently, this means that Class 1 and 2 eBikes are now permitted on more than 75 miles of paved Orange County regional bikeways. Due to safety concerns, all classes of eBikes continue to be prohibited on unpaved trails within regional and wilderness parks.

December 4, 2015 
Polyphagous Shot Hole Borer in OC Parks Trees

The Polyphagous Shot Hole Borer (PSHB) is an invasive beetle that attacks common native and landscape trees, leading to branch dieback and overall decline. This can have a devastating effect on local trees, and you may see some being treated or removed in County parks.

February 9, 2015 
Invasive Pest Found in Orange County

Gold Spotted Oak Borer (GSOB), an invasive beetle that has killed thousands of oak trees in San Diego and Riverside counties in a short span of time, has now been detected in Orange County. The GSOB was discovered in approximately 60 trees on County park land in northern Orange County. Since GSOB is transported in oak firewood, it is critical that Californians keep firewood local and not move it out of the area.

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