Your adventure guide to Irvine open space

The Irvine Ranch Southern Open Space Preserve encompasses some of the most picturesque environments in Southern California.

Irvine’s Southern Open Space Preserve is a remarkable window into one of the rarest ecosystems on Earth.

Stretching 16 miles from Irvine’s Quail Hill to the Pacific Ocean, it offers a vibrant tapestry of natural habitat, from meadows to woodlands to breezy ridgelines sequined with coastal sage scrub. This stunning 15,000-acre expanse (almost twice the size of Seal Beach) is home to dozens of plants and animals that exist nowhere else in the world.

The preserved coastal hills offer a variety of public trails, including one from Bommer Canyon in Irvine that extends to the sandy beaches of Crystal Cove. Rare birds you might see on the trails include the California gnatcatcher and cactus wren. Rare plants include the Catalina mariposa lily and many-stemmed dudleya.

When you step onto 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 this landmark is available for discovery and enjoyment by Californians … forever.



  • New hiking trails

    Civic leaders and outdoor enthusiasts celebrate the opening of Red Rock Wilderness area, now available for you to enjoy.

  • 10,000 STEPS

    Start your day with a relaxing hike at Bommer Canyon.

  • The view is good from the top

    Irvine’s park system has been named No. 1 in California and No. 4 in the United States by the Trust …

  • 10,000 steps at Mason Regional Park 

    A 9-acre lake, popular among model sailboaters, is just one of many attractions at the 339-acre William R. Mason Regional Park. …