Enjoy the relaxation of riding in the wilderness on empty trails. Join us on this docent-led mountain bike ride through Limestone Canyon, part of OCParks’ Irvine Ranch Open Space. We will visit the East Viewing Platform for a panoramic view of the geological feature call The Sinks. The route to The Sinks will include a fun downhill ride on the Dripping Springs single track. The return route will take us on the Limestone Ridge single track with views of Limestone Canyon, Santiago Canyon and the Santa Ana Mountains.

This is a slow-paced ride designed for the beginner that has experience riding fire roads such as Limestone Canyon or Telegraph Canyon but wants to develop their climbing and riding abilities. The ride can also be enjoyed by more advanced riders looking for a relaxed ride in a beautiful setting.

Reviewing the 1-through-5 Difficulty Ratings will help you evaluate your readiness to participate in this level-3 activity on the land. Please visit our FAQ page for answers to activity specific questions you may have prior to registering. Motorized recreation vehicles of any class or type are not permitted for use in the Nature Preserve.

Please note that you will be asked to adhere to the following measures in order to participate:

• Be registered in advance, no walk-up registration is permitted.
• Arrive with all necessary equipment to keep you safe on the trail, including water, proper attire, and closed-toe footwear, first aid, health needs etc.
• Restrooms will be available, but facilities will not be sanitized for each individual.
• All participants are required to sign a liability waiver upon arrival at the staging area and before beginning the activity. The waiver can be previewed here: IRC Liability Waiver
• You may be prevented from participating if you do not adhere to the above protocols.

Additionally, in an effort to respect and protect all employees, volunteers, and participants, please do not sign up or attend if you are not feeling well, exhibiting any symptoms of illness or have been in recent contact with someone who was ill.

Learn more and register here

PRE-REGISTRATION is REQUIRED for this event. 

All participants are required to have, a printed copy or on their phone, the confirmation email to show through the window of their vehicle to drive through the entry gate.

You will need the confirmation email for you and your guests to enter the trail system.

Come experience Limestone Canyon’s beauty from the back of your horse. Designated trails will be open for self-guided access hiking, biking, and equestrian use during Wilderness Access Day in Limestone Canyon. Equestrian riders who have trail riding experience with a fit and able horse will enjoy the historic ranch roads of days gone by. Take in the awe-inspiring vistas from the mighty ridge tops and drink in the cool canyon shade through the oak grove.

There is limited space for equestrian parking. Riders must also have the ability to transport their horse to the staging area.

Please note that you are asked to adhere to the following measures during the activity in order to participate:

• Arrive with all necessary equipment to keep you safe on the trail, including water, proper attire, and footwear, first aid, medications, etc.
• Restrooms will be available, but facilities will not be sanitized for each individual.

Additionally, in an effort to respect and protect all employees, volunteers, and participants, please do not sign up or attend if you are not feeling well, exhibiting any symptoms of illness or have been in recent contact with someone who was ill.

Do not stop or park anywhere along Santiago Canyon Road. The entrance gate will not open until 8am.  Anyone stopped or parked along Santiago Canyon Road prior to the opening will be subject to citation. Thank you for your cooperation with regard to the safety of everyone on the road. Please plan your drive accordingly.

Participants are required to stay on designated trails at all times. In addition to being a rare and sensitive habit, the Irvine Ranch Open Space is under strict protection. There are often unseen dangers just off-trail including, but not limited to: mountain lions, poison oak, ticks, poisonous spiders, and venomous snakes. OC Parks Rangers may issue citations for visitors found off-trail so for your safety, please stay on the designated paths during your stay in Limestone Canyon. To learn more about the staging areas and activity locations, please visit our Staging Areas Playlist page.

Other Important Notes:

• Visiting the highly popular “The Sinks” is a 9-mile round trip hike over moderate terrain and can take the majority of the designated event time.
• OC Park Rangers require all trails to be cleared for closure by 2:00pm.
• No new trail users will be permitted onto the trails at least one hour prior to closing.
• Dogs are prohibited on the Irvine Ranch Open Space. No matter how cute yours may be, by nature, dogs are predators; their presence and their lingering scent disturb the indigenous wildlife and disrupt vital routines long after a dog has left the area.
• Minors, ages 18 and under, must be registered by a parent or guardian.
• Adult mountain bikers and equestrians are requested to wear helmets. Minors are required to wear helmets per state law.
• Once registered, please email info@irconservancy.org at least 72 hours prior to the event so that we may verify whether your trailer can be accommodated in our parking configuration. Trailer parking is very limited and is subject to “first come, first served.”
• Inclement weather or fire danger will cause the program to be cancelled.

Multi-use trail etiquette: Please Remember that bikers yield to hikers and that bikers and hikers yield to equestrians. Click here for more trail tips.

To minimize the human impact on wildlife and their habitat, there may be unannounced trail closures or the rotation of areas being open and closed. This is an adaptive management approach to accommodate both the human users and wildlife needs.

To learn more about the staging areas and activity locations, please visit our Staging Areas Playlist page

Learn more and register here

Join us on this moderate-paced hike over the ridge and the through beautiful Limestone Canyon Nature Preserve, part of OC Parks’ Irvine Ranch Open Space. We will enjoy short breaks at the East and West Sinks viewing platforms before hiking back through the canyon. We will enjoy a view of wonderful vistas in addition to a spectacular view of The Sinks. This hike involves hiking on both double and single-track trails with an elevation gain of 1000 ft.

Please come prepared with a sturdy day pack, water, snacks, closed-toe hiking shoes or boots, sunscreen, first aid, and all other supplies to keep you safe and healthy on the trail on this half-day hike in the wilderness area. Under-prepared hikers may be denied access to the event.

Please note that you will be asked to adhere to the following measures in order to participate:

• Be registered in advance, no walk-up registration is permitted.
• Arrive with all necessary equipment to keep you safe on the trail, including water, proper attire, and closed-toe footwear, first aid, health needs etc.
• Restrooms will be available, but facilities will not be sanitized for each individual.
• All participants are required to sign a liability waiver upon arrival at the staging area and before beginning the activity. The waiver can be previewed here: IRC Liability Waiver
• You may be prevented from participating if you do not adhere to the above protocols.

Additionally, in an effort to respect and protect all employees, volunteers, and participants, please do not sign up or attend if you are not feeling well, exhibiting any symptoms of illness or have been in recent contact with someone who was ill.

Reviewing the 1-through-5 Difficulty Ratings will help you evaluate your readiness to participate in this level-4 activity on the land. Please visit our FAQ page for answers to activity specific questions you may have prior to registering.

Learn more and register here

Looking for a way to give back to Nature this Autumn? Come help us behind the scenes at the Irvine Ranch Conservancy’s one-of-a-kind Native Seed Farm in Irvine! Every day at the farm is different; depending on the needs of the farm we will be harvesting seeds, weeding, trimming, or planting seed of our beautiful native plants.

Working with us at the Native Seed Farm is a great way to grow your community and cultivate knowledge about local native plants, ecology, and wildlife! Absolutely no experience or special equipment required! 

The seed collected will be used for habitat restoration within the Irvine Ranch Natural Landmarks. These plants were specially selected to support local wildlife and promote resilience in the ecosystem. Come help us heal the wildlands within the Landmarks! When you sign up, check the confirmation email to see tips on how to be prepared for your time with us.

Please note that you will be asked to adhere to the following measures in order to participate:

• Be registered in advance, no walk-up registration is permitted.
• Arrive with all necessary equipment to keep you safe, including water, snacks, sun protection, long pants, closed-toe footwear, first aid, health needs etc.
• Restrooms will be available, but facilities will not be sanitized for each individual.
• All participants are required to sign a liability waiver upon arrival at the staging area and before beginning the activity. The waiver can be previewed here: IRC Liability Waiver
• Please note our Minors Policy for all public activities: All minors (under 18 years of age) must be accompanied by their respective parent or legal guardian. Both parent and their accompanying minor(s) must be registered for the Irvine Ranch Conservancy led activity they wish to attend.
  • Minors must be 8 years of age or older to participate in activities at the Native Seed Farm.

Note: Activity leaders may turn away participants who are under-prepared and wearing improper attire for work at the Native Seed Farm. This is for your own safety and to ensure an enjoyable experience for everyone who attends.

Additionally, in an effort to respect and protect all employees, volunteers, and participants, please do not sign up or attend if you are not feeling well, exhibiting any symptoms of illness or have been in recent contact with someone who was ill.

Reviewing the 1-5 Difficulty Ratings will help you evaluate your readiness to participate in this Level 2 activity. Activities may include bending, stooping, crouching, squatting, long periods of standing, reaching, pulling, grabbing, and pushing.

Learn more and register here

Join us in OC Parks’ Irvine Ranch Open Space for a challenging docent-led mountain bike ride for very experienced off-road riders in excellent cardio shape. Climb challenging State Spur to Cathedral Rock, and then descend into Fremont Canyon while passing some of Orange County’s most spectacular geological formations. The ride continues out to Mini-Moab and then over to Sierra Peak, passing the Tecate Cypress forest, then past Sierra Peak, and over to the last descent down through historic Black Star Canyon. Motorized recreation vehicles of any class or type are not permitted for use in the Nature Preserve. 

Please note that you will be asked to adhere to the following measures in order to participate:

• Be registered in advance, no walk-up registration is permitted.
• Arrive with all necessary equipment to keep you safe on the trail, including water, proper attire, and closed-toe footwear, first aid, health needs etc.
• Restrooms will be available, but facilities will not be sanitized for each individual.
• All participants are required to sign a liability waiver upon arrival at the staging area and before beginning the activity. The waiver can be previewed here: IRC Liability Waiver
• You may be prevented from participating if you do not adhere to the above protocols.

Additionally, in an effort to respect and protect all employees, volunteers, and participants, please do not sign up or attend if you are not feeling well, exhibiting any symptoms of illness or have been in recent contact with someone who was ill.

Please note that the direction of travel on the loop is subject to change at the docent’s discretion.

Reviewing the 1-through-5 Difficulty Ratings will help you evaluate your readiness to participate in this level-5 activity on the land. Please visit our FAQ page for answers to activity specific questions you may have prior to registering. To learn more about the staging areas and activity locations, please visit our Staging Areas Playlist page.

Learn more and register here

As the day starts to settle into the night in OCParks’ Irvine Ranch Open Space, bats awaken, stir and streak into the evening sky. Come hear fascinating tales of our flying mammals. We will head out towards a popular roosting location as we watch our nighttime heroes begin their nightly adventures. This program is ideal to visually observe the bats in flight, though bat detectors are available to listen for their high-frequency calls. Be prepared to walk about 1/2 a mile. Dress warmly as it may be a chilly evening. A camping chair is welcome as we will enjoy an extended period of time listening for bats that fly about in the night.

Please note that you will be asked to adhere to the following measures during the activity in order to participate:

• Be registered in advance, no walk-up registration is permitted.
• Arrive with all necessary equipment to keep you safe on the trail, including water, proper attire, and closed-toe footwear, first aid, health needs etc.
• Restrooms will be available, but facilities will not be sanitized for each individual.
• All participants are required to sign a liability waiver upon arrival at the staging area and before beginning the activity. The waiver can be previewed here: IRC Liability Waiver
• You may be prevented from participating if you do not adhere to the above protocols.

Children under the age of 5 are permitted to attend the hike if they are secured in a carrier or all terrain stroller for the duration of the hike.

Additionally, in an effort to respect and protect all employees, volunteers, and participants, please do not sign up or attend if you are not feeling well, exhibiting any symptoms of illness or have been in recent contact with someone who was ill.

Reviewing the 1-through-5 Difficulty Ratings will help you evaluate your readiness to participate in this level-1 activity on the land. Please visit our FAQ page for answers to activity specific questions you may have prior to registering.

Learn more and register here

Looking for a way to give back to Nature this Autumn? Come help us behind the scenes at the Irvine Ranch Conservancy’s one-of-a-kind Native Seed Farm in Irvine! Every day at the farm is different; depending on the needs of the farm we will be harvesting seeds, weeding, trimming, or planting seed of our beautiful native plants.

Working with us at the Native Seed Farm is a great way to grow your community and cultivate knowledge about local native plants, ecology, and wildlife! Absolutely no experience or special equipment required! 

The seed collected will be used for habitat restoration within the Irvine Ranch Natural Landmarks. These plants were specially selected to support local wildlife and promote resilience in the ecosystem. Come help us heal the wildlands within the Landmarks! When you sign up, check the confirmation email to see tips on how to be prepared for your time with us.

Please note that you will be asked to adhere to the following measures in order to participate:

• Be registered in advance, no walk-up registration is permitted.
• Arrive with all necessary equipment to keep you safe, including water, snacks, sun protection, long pants, closed-toe footwear, first aid, health needs etc.
• Restrooms will be available, but facilities will not be sanitized for each individual.
• All participants are required to sign a liability waiver upon arrival at the staging area and before beginning the activity. The waiver can be previewed here: IRC Liability Waiver
• Please note our Minors Policy for all public activities: All minors (under 18 years of age) must be accompanied by their respective parent or legal guardian. Both parent and their accompanying minor(s) must be registered for the Irvine Ranch Conservancy led activity they wish to attend.
  • Minors must be 8 years of age or older to participate in activities at the Native Seed Farm.

Note: Activity leaders may turn away participants who are under-prepared and wearing improper attire for work at the Native Seed Farm. This is for your own safety and to ensure an enjoyable experience for everyone who attends.

Additionally, in an effort to respect and protect all employees, volunteers, and participants, please do not sign up or attend if you are not feeling well, exhibiting any symptoms of illness or have been in recent contact with someone who was ill.

Reviewing the 1-5 Difficulty Ratings will help you evaluate your readiness to participate in this Level 2 activity. Activities may include bending, stooping, crouching, squatting, long periods of standing, reaching, pulling, grabbing, and pushing.

Learn more and register here

Do you want to explore the Sinks, a geological rock formation that has got its reputation as “Orange County’s miniature Grand Canyon”? Come out and join us on a hike from the Portola staging area to the West Sinks in OC Parks’ Limestone Canyon. Distance is about 6 miles, with some sustained climbing in one section. Participants must wear sturdy, closed-toe hiking shoes. Remember to pack plenty of water, sunscreen, a hat, and all other necessary equipment to keep you safe on the trail. This activity originates in the City of Irvine (Portola Staging Area) and travels into OC Parks’ Irvine Ranch Open Space.

Please note that you will be asked to adhere to the following measures in order to participate:

• Be registered in advance, no walk-up registration is permitted.
• Arrive with all necessary equipment to keep you safe on the trail, including water, proper attire, and closed-toe footwear, first aid, health needs etc.
• Restrooms will be available, but facilities will not be sanitized for each individual.
• All participants are required to sign a liability waiver upon arrival at the staging area and before beginning the activity. The waiver can be previewed here: IRC Liability Waiver
• You may be prevented from participating if you do not adhere to the above protocols.

Additionally, in an effort to respect and protect all employees, volunteers, and participants, please do not sign up or attend if you are not feeling well, exhibiting any symptoms of illness or have been in recent contact with someone who was ill.

Reviewing the 1-through-5 Difficulty Ratings will help you evaluate your readiness to participate in this level-4 activity on the land. Please visit our FAQ page for answers to activity specific questions you may have prior to registering. To learn more about the staging areas and activity locations, please visit our Staging Areas Playlist page.

Learn more and register here

Come explore Gypsum Canyon Wilderness, the northernmost portion of OC Parks’ Irvine Ranch Open Space. This scenic hike involves steepish climbs and descents on several single-track trails and is done at an average moving pace of 3 miles per hour. The rewards are many: panoramic views of Fremont and Weir Canyon Nature Preserves and beyond, possible wildlife sightings, interesting rock formations, and beautiful wildflowers in season.

Please come prepared with a sturdy day pack, water, snacks, closed-toe hiking shoes or boots, sunscreen, first aid, and all other supplies to keep you safe and healthy on the trail. All participants must carry their own day pack and water and be comfortable hiking an average moving pace of 3 miles per hour. Underprepared participants may be denied access to this activity.

Please note that you will be asked to adhere to the following measures during the activity in order to participate:

• Be registered in advance, no walk-up registration is permitted.
• Arrive with all necessary equipment to keep you safe on the trail, including water, proper attire, and closed-toe footwear, first aid, health needs etc.
• Restrooms will be available, but facilities will not be sanitized for each individual.
• All participants are required to sign a liability waiver upon arrival at the staging area and before beginning the activity. The waiver can be previewed here: IRC Liability Waiver
• You may be prevented from participating if you do not adhere to the above protocols.

Additionally, in an effort to respect and protect all employees, volunteers, and participants, please do not sign up or attend if you are not feeling well, exhibiting any symptoms of illness or have been in recent contact with someone who was ill.

Reviewing the 1-through-5 Difficulty Ratings will help you evaluate your readiness to participate in this level-4 activity on the land. Please review our Trail Tips and FAQ pages to ensure you arrive prepared for this hike.

Learn more and register here

Take a leisurely ride on beautiful Hall Canyon and Helo trail in the Black Star Wilderness Area, home of oak woodlands, grasslands, and coastal sage scrub. View evidence of the old ranch days when cattle once roamed the area and see wildflowers that are native to our area. You will see amazing views of the local canyons and red rock. Evidence of a more recent use of the land is an area used for helicopter landings and a large metal ball and chain the military and OC Fire departments used for training.

Equestrians who have trail riding experience, and their own fit and able horse are welcome. You will need to transport your horse to the staging area. Owners of unshod horses, please note that footing will include areas of gravel, rocky creek areas.

Please note that you will be asked to adhere to the following measures in order to participate:

• Be registered in advance, no walk-up registration is permitted.
• Arrive with all necessary equipment to keep you safe on the trail, including water, proper attire, and closed-toe footwear, first aid, health needs etc.
• You are welcome to arrive 30 minutes prior to listed departure time to ready your horse.
• We will be contacting you for trailer details so we can give you direction on where to park it.
• Restrooms will be available, but facilities will not be sanitized for each individual.
• All participants are required to sign a liability waiver upon arrival at the staging area and before beginning the activity. The waiver can be previewed here: IRC Liability Waiver
• You may be prevented from participating if you do not adhere to the above protocols.

Additionally, in an effort to respect and protect all employees, volunteers, and participants, please do not sign up or attend if you are not feeling well, exhibiting any symptoms of illness or have been in recent contact with someone who was ill.

Reviewing the 1-through-5 Difficulty Ratings will help you evaluate your readiness to participate in this level-3 activity on the land. Please visit our FAQ page for answers to activity specific questions you may have prior to registering.

Learn more and register here