Irvine’s ‘Grand Canyon’

The 20-million-year-old, red-sandstone cliffs of Limestone Canyon are a natural wonder right in Irvine’s backyard. The canyon is part of part of 57,500 acres of open space that Irvine Company has dedicated for permanent preservation and public access. The company also contributed $50 million for the land’s long-term care and management.


Exploring Limestone Canyon

Hike: Choose from more than 20 monthly hikes – slow walks to cardio workouts – going to Loma Ridge, Dripping Springs and The Sinks, a 10-mile round trip.


Bike: Weekly bike rides include slow-paced family rides (with stops to discuss habitat and wildlife), intermediate evening rides, and advanced rides on steep terrain.


Learn: Irvine Ranch Conservancy offers a variety of free programs: Learn to be a better birder or nature photographer. Or walk through oak groves and hear how Native Americans used acorns. See details below.


Q&A: Irvine Ranch Conservancy

Michael O’Connell, President & CEO of Irvine Ranch Conservancy, describes the natural beauty of Limestone Canyon and IRC’s role in protecting it for future generations.

Describe Limestone Canyon.

It has so much to offer: stands of oak and sycamore trees, spring wildflowers, cactus, mule deer, bobcats, red-tailed hawks and woodpeckers. Then there’s The Sinks, known as our local Grand Canyon.

Why is it called The Sinks?

Scientists have evidence it formed during a large geological event that caused the entire hillside to fall off, or sink.

How can people see it?

There are two viewing decks – each about a 4-mile hike from the trailhead. The East Sinks viewing deck offers more expansive views of the entire landscape; the West Sinks viewing deck brings you right to the edge for a great view of the canyon below and often cool breezes off the ocean.

What do visitors say about it?

These lands are like having a national park experience in our backyard.

What is IRC?

We are a nonprofit organization that helps manage nearly 30,000 acres of wildlands and open space on behalf of public landowners such as OC Parks and the cities of Irvine and Newport Beach. Our mission is to protect, restore and enhance the natural resources of these areas and help people connect with the land through volunteerism and activities.

*Note: All IRC events are free and docent-led with limited capacity, except every- other-month Wilderness Access Days. The next one in Limestone Canyon is Dec. 7.

Learn more about activities on the land at letsgooutside.org/activities.