The Irvine Ranch Northern Open Space Preserve delivers a wilderness experience unlike any in Orange County.


Irvine’s Northern Open Space Preserve provides residents an opportunity to visit 20,000 acres of pristine wilderness, just moments from home.

It begins its ascent above the villages of Portola Springs and Orchard Hills and reaches across four canyons on its way to Cleveland National Forest. Along the way, it passes mountains, meadows, lakes, waterfalls and woodlands.

Highlights include Limestone Canyon with its 40-million- year-old sandstone cliffs; Fremont Canyon, bright with poppies each spring; Weir Canyon, home to mule deer and oak woodlands; and Black Star Canyon, where golden eagles soar.

The open space offers a variety of OC Parks trails through habitats of rare species, from the California gnatcatcher to the world’s northernmost stand of Tecate cypress trees. You can access these wonders through guided tours by the Irvine Ranch Conservancy.

When you step into the preserve, you enter the largest urban open space network in America – the only land ever to receive both the California State and United States National Natural Landmark designation. And it is available for all residents to enjoy forever.

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