The activities below are offered by a variety of organizations and their dedicated volunteers. All programs are FREE unless noted below. Programs led by IRC-Certified Volunteers require pre-registration, which closes at 4 p.m. on the day prior to the event. No walk-up registrations will be permitted for these events. For policies of other organizations, please use the sign-up information provided. For mobility device policies click here.
Note: Minors must be accompanied by a parent or guardian for these events. For programs requiring online registration, each adult and child must be registered. |
Need help? For the fastest answers, look for organization-specific contact information in each event listing (click More Information for full listing). If no contact information is listed, email info@irconservancy.org for assistance.
Updated Difficulty Ratings: The Hiking and Fitness Difficulty Ratings have been updated to reflect our current activities. Please click below to read the ratings.
Click here to learn more about IRC-Certified Volunteers. • Click here to learn more about the Difficulty Ratings.
Search & Filter Activities
Monday, March 17, 2025
Chilly Birds of Winter in Limestone Canyon – Bird Walk

Birds are among the most colorful and entertaining forms of wildlife on the Irvine Ranch Natural Landmarks. Bring your binoculars and join us on a slow/medium paced walk in OC Parks’ Limestone Canyon, as we search for resident and visiting birds of the local coastal sage scrub, oak woodland, riparian, and grassland habitats. We will discuss the diverse features of the birds we observe and how they match the season, their habitat and lifestyle. We will travel mostly on ranch roads, usually without shade. Beginners to advanced bird enthusiasts are welcome. Please wear sturdy shoes suitable for hiking and bring water, along with sun protection such as a hat and sunscreen. Bring a small birding field guide if you have one. A few binoculars will be available to borrow.
Tuesday, March 18, 2025
Tuesday Morning Fitness Hike on Paved Hicks Haul Road

Ready for a workout? Forget the gym for the day and head outside! Join us for an exhilarating morning fitness hike on the paved Hicks Haul Road in OC Parks’ Irvine Ranch Open Space. This hike allows you to choose between a 3, 6, or 8 mile route, all of which are conducted at the speed of about 3.0 to 3.5 miles per hour. The footing on the asphalt paved road is smoother than dirt roads and single track trails normally found in Limestone Canyon Nature Preserve, but is beginning to show its age with cracks, crevices and an occasional dip. Otherwise, the terrain is smooth, so this is a great walk for anyone who wants a “wilderness experience” without getting dirty! The 6 and 8 mile routes experience two fairly steep ascents and descents. The 3 mile route takes you to the top of Loma Ridge and back down. Along the way, you will have sweeping views of much of Orange County and the Santa Ana Mountains. Various animals, like hawks, deer, and lizards are also frequently seen in this area.
Evening Hike on Hicks Haul Road

Enjoy an evening hike through stunning rock formations and fragrant native plants as you listen to the sounds of nature. During this hike in the Irvine Open Space Preserve, you may travel at various hiking speeds based on your comfort level. This out-and-back program travels 3.5 miles round trip up to scenic Loma Ridge and back down. Please bring a red-tinted flashlight as the return portion of the hike may be after sunset.
Wednesday, March 19, 2025
After Work Fitness Hike on Paved Hicks Haul Road

Join us every Wednesday night in OC Parks’ Irvine Ranch Open Space for a fitness-focused hike on the paved Hicks Haul Road. During the spring, summer and fall, hikers will enjoy wonderful sunset views and a panoramic overview of Orange County. This hike travels about 3.5 miles, up to the top of Loma Ridge and back down. The hike is conducted at an average of 3-3.5 miles per hour, but you may travel a bit faster or slower, at a walk, run, or jog depending on your comfort level. Most participants finish the route in about 1 hour. Because of the paved surface of the road, you may wear regular running or walking shoes. Trail shoes are fine, but not required. Please bring adequate water.
Saturday, March 22, 2025
Advanced Cardio Hike: Limestone

Join us for a strenuous, extremely challenging, fast-paced, early morning cardio hike in Limestone Canyon, part of OC Parks’ Irvine Ranch Open Space. Along the way we’ll be rewarded with panoramic views of Orange County and possible wildlife sightings. This is an 8 mile cardio hike, completed in 2.5+ hours, includes a 1000+ foot elevation change. This hike is for experienced, physically fit hikers who enjoy the challenge of multiple steep climbs and descents. This hike is much faster than a regular walking hike. We average four (4) miles per hour fast-paced and is extremely difficult over steep terrain in the wilderness setting.
Sunday, March 23, 2025
Orange County Bird of Prey Center’s Raptor Ecotrek

Your journey begins with an exclusive, up-close introduction to the Education Ambassadors of the Orange County Bird of Prey Center—a dedicated wildlife rehabilitation organization that rescues and releases injured owls, eagles, hawks, and falcons. These remarkable birds, unable to return to the wild due to injuries or behavioral challenges, now serve as ambassadors for their species. You’ll have the rare opportunity to observe them up close, learn about their unique adaptations and hunting styles, and, of course, snap some incredible photos!
Next, hop into a 4-wheel drive vehicle for a scenic 9-mile tour through the stunning, secluded Limestone Canyon Nature Preserve. Along the way, we’ll pause to soak in panoramic views, capture memorable photos, and keep an eye out for wild raptors soaring overhead.
Our adventure culminates at The Sinks, often called the “Grand Canyon of Orange County.” Here, we’ll enjoy a delicious box lunch surrounded by breathtaking natural beauty. The highlight of the day? One lucky participant will have the once-in-a-lifetime opportunity to release a rehabilitated raptor back into the wild—an awe-inspiring moment that everyone will get to witness.
This is a rare and extraordinary experience you won’t want to miss!
For registration, visit the Orange County Bird of Prey Center.
Evening Family Beginner Mountain Bike Ride: Limestone Canyon to The Sinks

For families and children ages 12 and up who would like to join IRC-certified volunteers in OC Parks’ Irvine Ranch Open Space on a longer, slow-paced, family-oriented ride through sycamores, oaks, and habitat native to California. The route takes us to The Sinks, Orange County’s own “Grand Canyon.” Along the way, we will stop and talk about the local habitat, and hope to see some of our local native animals and raptors. The ride is an 8-9 miles with 400-800 feet of elevation gain that may require hike-a‐bike for some riders. Motorized recreation vehicles of any class or type are not permitted for recreational use.
Monday, March 24, 2025
Monday Morning Super Trek: Limestone Canyon to Box Springs and the Sinks

Come start your week with us on our Super Treks in the Landmarks. Join us as we explore Limestone Canyon, part of OC Parks’ Irvine Ranch Open Space. We will hike across East Loma and enjoy beautiful views of the surrounding hills, out to the coast, and of Irvine Lake. We will continue to Box Springs and the west side of the Sinks before making our return to the staging area. Please wear hiking shoes/boots and bring water, a trail snack, sunscreen, hat, and any other necessary equipment to keep you safe on the trail. Participants must be able to hike 11 miles with an elevation gain of 1800 feet at an average moving rate of 3 miles per hour.
Tuesday, March 25, 2025
Tuesday Morning Fitness Hike on Paved Hicks Haul Road

Ready for a workout? Forget the gym for the day and head outside! Join us for an exhilarating morning fitness hike on the paved Hicks Haul Road in OC Parks’ Irvine Ranch Open Space. This hike allows you to choose between a 3, 6, or 8 mile route, all of which are conducted at the speed of about 3.0 to 3.5 miles per hour. The footing on the asphalt paved road is smoother than dirt roads and single track trails normally found in Limestone Canyon Nature Preserve, but is beginning to show its age with cracks, crevices and an occasional dip. Otherwise, the terrain is smooth, so this is a great walk for anyone who wants a “wilderness experience” without getting dirty! The 6 and 8 mile routes experience two fairly steep ascents and descents. The 3 mile route takes you to the top of Loma Ridge and back down. Along the way, you will have sweeping views of much of Orange County and the Santa Ana Mountains. Various animals, like hawks, deer, and lizards are also frequently seen in this area.
Dripping Springs Trail Restoration

Spend the morning watering and mulching Coast Live Oak seedlings within a beautiful oak woodland and then hike to Dripping Springs, a natural water source dripping out of an earthquake fault and down a gorgeous fern-covered rock face. Your work on the trail will benefit the rare plants and animals that this unique feature supports!
Evening Hike on Hicks Haul Road

Enjoy an evening hike through stunning rock formations and fragrant native plants as you listen to the sounds of nature. During this hike in the Irvine Open Space Preserve, you may travel at various hiking speeds based on your comfort level. This out-and-back program travels 3.5 miles round trip up to scenic Loma Ridge and back down. Please bring a red-tinted flashlight as the return portion of the hike may be after sunset.
Wednesday, March 26, 2025
Seasonal Science Series: Intro to iNaturalist at the Butterfly Enhancement Project

Join us for a hike related to current IRC projects focused on research, monitoring, and conservation. The series will rotate through the landscape based on the season and projects.
For this series, we will spend the morning hiking along Limestone Canyon where we will look for plants and animals and learn how to identify them using the iNaturalist app. For this activity you will need to download the free app on your smart phone BEFORE arriving to participate in the activity. We will stop at 2-3 butterfly plots for 5-10 minutes and using the app document the flora and fauna that we see. After we will finish with a hike up to Dripping Springs, a natural water source dripping out of an earthquake fault and down a gorgeous fern-covered rock face.
After Work Fitness Hike on Paved Hicks Haul Road

Join us every Wednesday night in OC Parks’ Irvine Ranch Open Space for a fitness-focused hike on the paved Hicks Haul Road. During the spring, summer and fall, hikers will enjoy wonderful sunset views and a panoramic overview of Orange County. This hike travels about 3.5 miles, up to the top of Loma Ridge and back down. The hike is conducted at an average of 3-3.5 miles per hour, but you may travel a bit faster or slower, at a walk, run, or jog depending on your comfort level. Most participants finish the route in about 1 hour. Because of the paved surface of the road, you may wear regular running or walking shoes. Trail shoes are fine, but not required. Please bring adequate water.
Saturday, March 29, 2025
OUTREACH: Field Trip for Delhi Center

IRC Volunteer support is needed to assist in a field trip for 10-15 students from Delhi Center (ages 13-19) to explore Limestone Canyon butterfly habitat islands. Students will develop their knowledge of native larval host and nectar source plants for different butterfly species in decline in Limestone Canyon. The activity will include walking about half a mile in from butterfly island to butterfly island.
Bus will arrive about 10:00 a.m. and depart by 12:00 p.m.
Support is needed to help work gates and aid in overall group management.
Contact Yezly at YFontalvo@irconservancy.org for more details.
Sunday, March 30, 2025
Photo Journey Limestone Canyon: The Sinks, Loma Ridge Backcountry and Sunset

Join us in the back-country wilderness for a journey filled with beautiful sights that are photographic and artistic sketching opportunities. Our journey begins in the afternoon. We will be deep in a secluded canyon, where time is measured in centuries, even millennia, in the sandstone cliffs of this ancient place called Limestone Canyon. You will board a 4-wheel drive vehicle for a 13-mile tour of the canyon and hills surrounding it. We will stop frequently for 15-30 minutes to admire the views, take photos, sketch landscapes, and answer questions.
Twilight Fitness Hike in Limestone Canyon

Limestone Canyon is a treasure waiting to be discovered. Join us for an afternoon, fast paced, 5.5-mile fitness hike with 750 ft of elevation. The hike will be a great introduction to fitness, cardio-style hikes as well as OC Parks’ magnificent Irvine Ranch Open Space. Views of Limestone Canyon, and the surrounding wilderness, from Limestone Ridge will be the highlight of our tour.
Tuesday, April 1, 2025
Tuesday Morning Fitness Hike on Paved Hicks Haul Road

Ready for a workout? Forget the gym for the day and head outside! Join us for an exhilarating morning fitness hike on the paved Hicks Haul Road in OC Parks’ Irvine Ranch Open Space. This hike allows you to choose between a 3, 6, or 8 mile route, all of which are conducted at the speed of about 3.0 to 3.5 miles per hour. The footing on the asphalt paved road is smoother than dirt roads and single track trails normally found in Limestone Canyon Nature Preserve, but is beginning to show its age with cracks, crevices and an occasional dip. Otherwise, the terrain is smooth, so this is a great walk for anyone who wants a “wilderness experience” without getting dirty! The 6 and 8 mile routes experience two fairly steep ascents and descents. The 3 mile route takes you to the top of Loma Ridge and back down. Along the way, you will have sweeping views of much of Orange County and the Santa Ana Mountains. Various animals, like hawks, deer, and lizards are also frequently seen in this area.
Evening Hike on Hicks Haul Road

Enjoy an evening hike through stunning rock formations and fragrant native plants as you listen to the sounds of nature. During this hike in the Irvine Ranch Open Space, you may travel at various hiking speeds based on your comfort level. This out-and-back program travels 3.5 miles round trip up to scenic Loma Ridge and back down. Please bring a red-tinted flashlight as the return portion of the hike may be after sunset.
Limestone and Red Rock Night Ride

Join us for an evening/night mountain bike ride through Limestone Canyon Nature Preserve and Red Rock Wilderness, part of OCParks’ Irvine Ranch Open Space. We will ride approximately 12 miles, with 1500′ of climbing along a variety singletrack trails and ranch roads. The route will vary based on trail conditions/availability.
This ride is not recommended as a first time night ride. Bring adequate lights, a jacket, plenty of water, spare tubes, tools and all other equipment to be self-sufficient on the trails. Hopefully we will see some of our local nocturnal critters. Motorized recreation vehicles of any class or type are not permitted for use in the Nature Preserve.
Wednesday, April 2, 2025
After Work Fitness Hike on Paved Hicks Haul Road

Join us every Wednesday night in OC Parks’ Irvine Ranch Open Space for a fitness-focused hike on the paved Hicks Haul Road. During the spring, summer and fall, hikers will enjoy wonderful sunset views and a panoramic overview of Orange County. This hike travels about 3.5 miles, up to the top of Loma Ridge and back down. The hike is conducted at an average of 3-3.5 miles per hour, but you may travel a bit faster or slower, at a walk, run, or jog depending on your comfort level. Most participants finish the route in about 1 hour. Because of the paved surface of the road, you may wear regular running or walking shoes. Trail shoes are fine, but not required. Please bring adequate water.